The overflow canister should really be called the expansion tank.

Coolant expands when hot, and the coolant goes into the tank. On cooldown, coolant is drawn back into the radiator for an air free system.

You cannot eliminate the cannister. This car will seriously overheat if it is ONE pint low on coolant.

 

Ok, understand. Will start the car this week WITH the canister.

 

Don't forget about the pressure build-up because of the radiator cap.
Without pressure you get a lower boiling point.

 

Yeah, I know. I use a FullBlown radiator as base and moved up the cap to stock location for filling.