Fixed thermostat - overdrive still funky! Wiring harness prices?

[joes240]

Hey all,

My thermostat was erratic, going up and down whenever I pressed the brakes. I fixed the problem I think, by cleaning up 2 terrible grounds where the paint wasn't even sanded off to make for good conduction.

I had my throttle position sensor re-calibrated a few days ago, and now my Overdrive only seems to make a difference when going 45mph or faster, is this normal? If going at slower speeds it doesn't seem to make much of a difference.

Also, how much should I look to spend on a new and/or used wiring harness? Any ideas?