At present I have a 01 cpu and would like to know if I can use a 03-04 cpu without the drive by wire and keep the same wiring harness as the 01. I have a lq9 , with a ls6 intake short tube headers and a tr 224 cam with a 3000 stall. no emmisions as it is in a 68 Impala. I was wanting to do this so I could see if I could use a ls2 program. Thanks Woody