yep your good.. it is a 81 300sd. I probably post too much on here but my car is in alot better shape then when i bought it. All thanks to people i bug on the forum.

I also tested the fan clutch it was fine. I just put in a new one around 5k miles ago. Could it maybe be too much straight coolant and not enough water... i had a leak in my hose one day and kept filling it with coolant instead of the mix.