i swapped in an Aristo vvti and mine is already an 03 manual. I used my stock harness and extended the MAF wires to reach the TB side (driverside) and have my MAF as a blow through 18" from TB in I/C pipe by lower frame rail. I have full access of OBDII port and have passed TN emissions. Only wiring mod i did was clone the B2S2 and B2S1 to read with B1S2 and B1S1. I also used a spark plug non fouler on the B1S2 (under car) to space out the 2nd O2 that way it sees less exhaust flow thus thinking there is still a converter on it. Wideband reads 10.8 or lower under a load, the ECU WILL compensate up to 13 lbs safely, anything more and the ecu can't add enough and starts to run closer to 12.1. No CEL's unless i turn the boost up and run it to death. I have driven my IS on several trips and the stock twins have the TTC mod and are at 13-15 lbs. has been reliable and get 20-24 mpg for the past 2 years. I just recently went to the single set up, Apexi Neo, and boost controller. Now that its at 15lbs daily, with as much as 18% correction it still runs at 10.8 - 11.4 WOT under a load. Dyno numbers were very impressive for stock motor with bolt on's.