Hello Davros, what an awesome write up! Maybe I'll follow your foot step when I start my Ke15.
By the way, most of our AE86 owners inlcuding myself are using brake callipars from Honda EG/EK, and vent disc from BMW E30. Both of them are easy to come by and cheap in Hong Kong. Not sure if this is the case where you are located. Those callipars shall fit nicely without mod, discs from BMW have to be drill. So far I'm pretty happy with the performance, and 14" rims can be fit without any trouble.
Anyway, keep up the good work.
Cheers,
Stan