I have an 88' 350 TBI engine in my 85' Blazer. I used a Painless wiring kit took hook it up. Now on the original wiring there was a disconnect on the Black/Tan?? wire going to the ignition mod. that would allow you to time the engine. I have been told and have briefly read about pluging into the 1st and Last port on the top of the ALDL will allow you to time the truck the same way is this true?? Or should i just cut the Black/Tan on the Painless that i have and just reconnected it when i am done??