First, what Microtech set-up should I get for the situation I am in?

Hi, I just recently swapped in an S5 89 j-spec turbo motor in to my s4 88 t2 and am still using the s4 wire harness. The engine starts and runs smooth above 1,500 rpm but loads with fuel and stalls below 500 rpm. After doing the extreme un-flooding procedure it does the same thing. I ran it till it was warm, and still the same. It was a complete engine with cut harness. I soldered the connectors from the cut harness to the old s4 harness on my car so the sensors would work on my new motor. What do you guys think? Maby the cold start system?

Also I disconnected the Oil Metering system and plan to mix 1oz of pre-mix to every gallon of gas.

-Thanks a lot
Dustin