harness question PLZ help

[1970 C10 MJW]

I am almost done depinning/ reorganizing my harness...a 1999 silverado 4.8l and I am trying to figure out what these 4 wires need to do...
first off my dad said they came from the fuse/relay panel two wires are a heavy gauge green, 1 is purple/white, and the last is yellow... all 4 of these wires go into the section of the harness for the transmission... both of the greens, the purple/white, and the yellow all go into the 6 pin transmission plug that was glues in from the factory... i will provide a pic here asap...