OK so I might have to come back to this a few times to add photos and edit it but here goes...
Turns out there's a few steps that make the process somewhat involved so I'll cover them separately. Also there are other ways to do this but this is what worked well for me.
1. Repinning the mirrors to suit the AUDM 8pin connectors (as opposed to the JDM 10pin connectors).
2. Running new wiring through the doors for the additional pins (mirror retract and mirror heating if you're have that also or you want to bother).
3. Rewiring the blue plug that goes into the back of the dash switch for the mirror retract button (this might be different for you if your car has VDC, mine didn't).
So the most important diagram I found is below. This is the bulk of what's needed.
Step 1.
If you look at the diagram, the AUDM models have a D5/D15 connector from the mirror with 5 wires. Thankfully the JDM mirrors maintain the same colours so I essentially repinned / transferred these over to the same spot on the AUDM connectors. Yes it means your old mirrors aren't too useful but I didn't have another option as my JDM mirrors did not come with the female connectors to allow soldering into the existing door wires.
Repinning is straightforward. Remove the plastic white tabs top and bottom, use pin/needle to get in to the connector and lift the tiny bit of plastic holding the connectors in place as you pull out on the wire. Take note of the orientation. Refer to the diagram but here are the numbers, colours and purpose of each of the wires in the 8-pin connector.
1 - White - Indicator + [ Turns into Red Black wire on female connector ]
3 - Blue - Mirror controls [ Turns into Red Blue wire on female connector ]
4 - Green - Indicator - [ Turns into Black wire on female connector ]
6 - Red - Mirror controls (Up/Down) [ Turns into Red Yellow wire on female connector ]
7 - Purple - Mirror controls (Left/Right) [ Turns into Red White wire on female connector ]
Ok so that gives you back what you had before on the mirror and now on to the retractor and heating. Look at the diagram again, and at the 10pin versions of D5/D15. Below are the pins and what the wires are for, you choice now to remove and pin them into the AUDM (but you'll be a pin short), keep them in the 10pin connector and just feed some wires in or transfer into another male + female connector for easy removal. Eventually we'll run new wires out the door to the all important i78 blue plug on the dash. From memory the retractable wires are grey and brown in the mirror and the heated wires are both black.
2 - Retractable mirror switch (leads to "13" on the i78 blue plug)
4 - Mirror heater circuit (should go to a mirror heater relay, I haven't actually hooked this up yet)
6 - Retractable mirror switch (leads to "4" on the i78 blue plug)
10 - Mirror heater circuit (leads to the common ground)
So now your mirrors should be mounted and ready for new wiring to go into the interior.
Step 2.
Running the wiring through the doors.
You'll want to remove the drivers side under dash panels (from the steering column down). Start at the bottom and there'll be 3-4 plastic pop-out plugs that will let you take out the panel near the pedals. It's worth taking the kick panels out as the door wiring / connectors exit out that way. The under dash panel with the mirror controls now just pops out from the dash at the top in 3-4 places. You'll need to unplug some connectors mostly around the old mirror controls. You'll see the blue i78 plug here too.
Not too deep behind the kick panels are the D83/D84 plugs. You'll need to disconnect these for a bit and pull them out so you can access the flexi / rubber conduit that the door cord wiring runs through. You might have to unbolt the mechanism that keeps the doors open so you can get a slight bit more angle / access. Next up remove the rubber conduit and pull the wiring through. This is done by pulling the rubber off the white plastic that keeps it in place (photos coming). Next pry the white plastic out a little with a flathead and push in the tabs holding it in place with another until it starts to come out. You might need to rotate it and do another one (there are three in total). Take note of the orientation as the rubber can only go back on in the same way.
With the wires pulled out you should have a bit more space to move the conduit so you can run wires through it. In the middle of the conduit you'll notice some electrical tape. Unwind it so you can pull back the flexible rubber conduit that leads to the door. This should reveal another smooth bit of rubber tubing that contains the wires right up until they split off to the various plugs in the door. I found the top of this tubing a good place to poke a firm wire down and out the other end. Using the wire you can temporarily tape your new wires and pull them through. Put back the door conduit as it was so it's concealing the new wires and tape it up again. Run all of the wires back into the cabin and clip in the other part of the conduit again (easier to put the rubber over the white plastic first and then push it through).
Reconnect the D83/D84 plugs and run the wires so they end up at the blue i78 plug. You'll need to solder the wires from the left and right too each other (2 to 2, 4 to 4, 6 to 6 and 10 to 10). Only one wire from the combined wires go to the i78 plug.
Step 3.
Connecting it up to the switch.
So as I mentioned, my car doesn't have VDC (Vehicle Dynamic Control - Traction Control effectively). So I already had some wiring in the i78 blue plug but none of it was in use and just went into a dummy switch on the back. This meant I could alter it as needed but it did uncover some additional problems, I didn't have enough wires again as my mirrors only had the switch and not the cut off i78 blue plug from the JDM wreck too. So not only did a discover I needed to shift some wires, I also needed to steal some others that would go into the plug. Thankfully some of the connectors from the stock macintosh speakers (which I'm not using) have the exact same terminals that can be pinned into the blue plug. Below are the wires and numbers for the i78 plug.
Refer to the diagram again for the number positions.
1 - Wiper de-icer switch (Orange Green in original AUDM plug) - removed.
2 - Wiper de-icer switch (Black in original AUDM plug) - move to position 11 (this is ground).
3 - Switch illumination (Black White) - leave it alone, still needed
4 - Retractable mirror switch - Plug in "6" wires from mirror here.
11 - Ground - Move what was originally the 2 position black wire here.
12 - ACC Power - Needed for the switch, splice this from the Yellow Black/Blue wire on plug i6 (the power mirror switch).
13 - Retractable mirror switch - Plus in "2" wires from mirror here.
14 - Illumination (Purple) - leave this alone, signal from when you turn your lights on.
Notes: The wiper de-icer circuit and button are useless to us, this is not the heated mirror circuit and is for models that have a de-icer built into the windscreen. The mirror heaters run off the same circuit as the rear demister. The ACC power from i6 is fine to use, it's on the same circuit and you can see this in the main diagram.
So that's essentially it apart from the mirror heater wiring and more images, these will come when I get some more time to update. It's straightforward just a bit time consuming. They work well although it's annoying that it's only under ACC power.