On the cooling system, I would pull the thermostat housing for cleaning. Flush the system without the thermostat in place. If mice have gotten into it, the thermostat may be (or get) clogged when you start the engine. The water pump is something you may want to keep an eye on and don't be surprised if it takes a crap shortly after you have run it a while.

I usually put a couple of quarts of Dextron II in the engine in place of a couple of quarts of engine oil to help clean and soften and lube seals. I don't drive it with that oil in it though. I change the oil again shortly after (maybe 30 minutes of run time) I get it running.

Good luck and keep us posted.
Builder

1960 Chevy Apache Shortbox
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