I just bought a 1986 Trans Am and the previous owner decided to do a motor swap from tbi to carb and they cut out the ecm and vss buffer. They cut the harness for both and I just got a new vss buffer for the car and I am left with just wires. I've been matching up wires in the back of the passager side engine bay and i believe i found the yellow and purple coming from the transmission and I have a ground and 12v power wire, but I can't find out which wire goes to the speedometer.

If anyone know what wires will give the speedometer life let me know and do i need to have the red or brown wire on the buffer hooked up to anything red is cruise control which i don't have and brown went to the ecm. Maybe I am missing something, but from what i've read as long as you have the vss buffer (yellow box the size of a deck of cards) the speedometer should work. Am I missing another step instead of just hooking up wires and hoping the speedometer will work.

Chris
1986 Trans Am