I wanted a six speed, but a V160 would be WAY too much $$$--so I went T56. In hind sight, an R154 would probably have been fine. It definitely would have been easier, and my drivetrain would have been all Toyota. Although it is cool to be cruising at 80 and be turning less than 2000 rpm.
I running 85mm pulley on pump & Meth at this stage, only got new combo running about 5 days before driving the car 3000klms down to Summernats to compete in the Burnout Masters, i was going for reliability so i could drive the 3000klms home again over outright power.
I do plan & putting the car back on the dyno soon with a 75mm pulley & Meth, I am still only expecting about 400 nth Qld hp at the wheels.