Hello wrc62!

I own ST170 and use it only for racing, trackdays etc, stock Getrag is too long and slow for me too so I'll do the same conversion soon... I already bought MTX75 with 4.06 final gear ratio and Quaife LSD.

As far as I know we need:

clutch/flywheel
gear selector and cables
driveshafts
maybe starter?

but what about vehicle speed sensor connected to the gearbox? It's different for sure and it will make some problems, did you think how to solve them? Do you use standalone management or stock ECU?