the japanese Mk3 supra came with a 1JZGTE, its a DOHC, 2.5l twin turbo engine.
Oppie is in the process of a 1JZ swap, with a single turbo in his Supra.
mostly a bolt in affair, but you have to do a harness conversion
you can either use the R154 5 speed, or be a baller and get the Getrag V160 6speed from the 2J.
people also sell TH350, TH400 kits for them.