Hi Baldy,
As far as I know the Foz can be fitted with Classic suspension but may be a tad too low.
All mounting points are exactly the same across all of the Impreza models.
I have had Bugeye and now got Hawkeye kit on and only difference was the brake pipe mounting brackets, my brake pipes are now secured to the struts using three large tie wraps around the pipe and mounting bracket, passed MOT no probs and still very secure.
I got my Hawkeye kit very, very cheap and just had to try it, and my luck was in.