Lean burn removal

I was laying on the intake manifold and hooked to the 12v Soldered wires. It wasn't hooked up to anything. The carb this truck is not a computer control carb, which doesnt make sense.
I have cut out the lean burn wiring minus the 12v hot i have found. Checked multiple wires for 12v start and it all comes back to this soldered one connected together.
Worst case is I throw in a HEI unit rigged to this 12v and go from there. I would like to do the mopar ECU but i just can't see where the second Start Wire is.

Thanks for your help...