Sam-
As for the overheating, I bet you have some air trapped in the manifold. I'm not sure if you tried this, but it worked on my car, either jack up the front of the car so that the front of the engine is higher than the back or park on a steep hill with the engine facing up hill and, with the car running, crack open the water temp fitting on the manifold and let all the air purge out until you get nothing but
antifreeze out of that fitting. You might have to do it a couple of times to get all the air out.