Turns out the idiot i bought the 350 from installed a harmonic balancer from a 70's 350 or something like that. ..thats not the greatest news because the guy claimed he put 10,000 miles on this engine, and i'm pretty sure the kind of vibration i was getting is NOT good for the bearings in the engine!
Only problem, when i was driving it back it started getting hot. By the time i got home the gauge read about 210 degrees. I am using the thermostat that came with the 350. It didn't look too great but i used it anyway, and seeing the STUPID things this guy did to the engine who knows what temp the thermostat is rated. I think im gunna use the one from my 305 and see how that goes. I'm also getting an electric fan soon...and radiator because my mechanic informed me it was leaking. It never ends! At least the biggest problems are behind me now.