Wiring help needed: rear defogger and switch

So I want to add the defogger and switch to my sons 1974 Laguna. I have the unit and switch, what I can't find is a diagram. Does anyone have a diagram or at least point me the way to wire this up. Not sure if there is a relay or where the 3 wiring ends from the switch go. Thanks for any help.
Gary

i have a harness. will try and get pics.

FWIW, from the Monte Carlo:

- Pink 16ga wire from fuse box ACC tap to center terminal of the defog switch, but with a 4A inline fuse along the way
- Purple wire from switch runs directly all the way back to the fan. This feeds full 12V to fan for high speed.
- Yellow wire leads to white resistance wire, which then splices into purple wire. This reduces voltage to provide low speed. If you don't have the resistance wire, you can probably splice in an actual resistor, but I don't know what the value should be.

Mark

Appreciate it, I think just to be simple I'm going to make it Hi/Hi and skip the low.