To answer the spark plug question helpfully, we need to know which type of cylinder head you're running. Is it a '60-'74 head (with the aluminum spark plug tubes and the gasket-seat plugs) or a '75-up head (without plug tubes and with the smaller taper-seat spark plugs)?
Thermostat: a Stant SuperStat 45358 (180°) or 45359 (195°) after reading
this.
