Ahk, previous owner did the conversion on my car and I got pinged at the pits for the crossmember not bolting up to all 4 holes. It sounds pretty picky but I'd like to fix it anyway regardless of the defect. Just learning now about all the RB crossmembers (A, B and C) and S13 crossmembers as well (also A, B and C).
I have done some research and looks like most people say an SR20 manual crossmember (labeled 'C') fits.