As far as wiring I was not sure if I could splice the harness my self so I gave Phoenix Tuning A call. They can do a complete harness conversion for you. You just send them your V8 harness and supra harness and it will be plug and play when you get it back. Now I am not getting payed to advertise for them or anything I was just really inpressed with there work. I had held off from telling people about them until i got my harness back just in case they did a crappy job. How ever the harness came back perfect and all re rapped for me. Totally worth the money to save all the PITA of harness splicing. I just use the 1uzfe computer and the engine harness plug right into the stock supra body harness. They even installed a tach converter for me. Hope this saves some people some time.
http://www.phoenixtuning.com/
http://www.phoenixtuning.com/