Pitroad TS Cup ports:

They (Pitroad) use an AE86 LSD in an alloy carrier H165 with 4.11 for Fuji and 4.635 for Tsukuba (in an iron carrier). They say H150 is prefferable for weight (4.0kg lighter) but it is hard to get ratios for them.
And a 56A Opt1 5spd
2.676
1.691
1.398
1.182
1.000

Info from here:
Pitroad B310 TS Cup infoYou could build a pretty good TS Cup replica from the detailled info they give! And spend a small fortune with them...