HEY ! Get in line ! LOL. So many people trying to sell used billies, and no-one in Brissie to buy mine

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I agree with Greenman. There's a guy over on OzFoz who bought a set for his SH. The front went in GREAT, but the eyelet size was different on the bottom of the rears, so he bought 09 STI WRX to match.
There's conjecture over them fitting to Gen 3s. I found a mechanic who has fitted all four gen IV billies to his gen 3, and has been driving it like that for some time. He says he simply had to swap the gen 3 top hats over on the fronts so they'd bolt in. And he claimed no discernable mismatch or change in ride height. However, someone else claimed that the billie top hats are uniquely shorter (mostly in the bearing thickness) and when he tried WRX (?) top hats, the top nut went on, but locked down still in the hollow top part of the shaft. This was considered weaker, and potentially dangerous, so carefull attention would need to be paid if attempted on a Gen 3.
In short, the fronts DEFINITELY fit and lower an SH9, the rears DEFINITELY fit a Gen 3. Everything else, you're a bit of a pioneer.