Thanks.
I can't help with the Gen5 specific stuff being a Gen4 owner, but there's a couple of things you could investigate. Firstly, you could look at modifying the brackets that hold the standard headunit to allow it to slide further back into the dash, allowing the tablet to sit in front of it, but still behind the fascia. I've seen this done quite well in a Forester (but can't recall what forum it was on, maybe NASIOC). Another option is to get rid of the stock headunit all together and run the tablet standalone. This can be done with a USB DAC and a small amplifier that you could mount behind the tablet where the headunit once was. That is assuming that your model doesn't have a factory amplifier. If it does, you could just run line level RCA's from the DAC to the factory amplifier (some custom cable splicing could be required).
Correct, the pre-facelift McIntosh doesn't have an high level AUX in, but even if it did, I prefer the FSL-21 method as it means I use a USB DAC, eliminating the amplifier in the tablet, meaning I get the best quality output possible. Many people are using the 3.5mm stereo option as it's very easy if your headunit has a 3.5mm in. But sound quality is the trade-off. Most would never tell without hearing the two side by side.
Thanks Chris... i like the idea of pushing the HU back... or even replacing it altogether. I'll take your advice and go the FSL way... better SQ is better SQ. How many low level outputs do you get this way? I was planning on getting a 4 channel amp... could remove the HU and fit the amp behind the tablet. Wondering if that would go well with this setup.