starter solenoid wires- which goes where?

[WIDESIDE72]

I recently bought a 72 Chevy c10 with no engine and trans. I am slowly getting it back together with a 30 and 700r4. I can't remember for the life of me which wire go where on the starter solenoid. It has been years since I swapped engines in a truck without an HEI. Since I didn't do the swap, I didn't pull everything, and the P.O. didn't label anything. THere is a yellow and a purple wire...Which goes where on the solenoid ?!?!