[blucar]

In my mind a coolant recovery tank is a must have item on just about any engine. The problem with the pre 48 engines is that the radiator fill cap generally has no allowance in the fill neck for a pressure cap to seat to therefore any expansion of the coolant spills onto the ground.
The first step to installing a coolant recovery systems is to improve the radiator and modify it with a neck that will seat a pressure cap.
Recovery tanks are very easy to make utilizing 12/18" of black 2" ABS pipe,two caps, one of which is glued on, the other is left loose. Two right angle barb/threaded 'Ell-bows, one of which is threaded into the glued on cap, the other threaded into the plastic tube, about 2" from the top. Attach clear plastic tubing to the bottom fitting, running it to the overflow neck of the radiator. attach a piece of clear tubing to the upper fitting on the ABS tube, extending the tubing down to the frame.
Secure the overflow tank verticilly with plumber tape.

To check the fluid level is very simple by viewing the fluid in the tubing, remove/replace the top cap to add fluid if needed. Once the system stabilizes, air is purged, adding fluid is not an everyday thing.
Of course you can go to the local speed shop, spending about $100. to purchase a nice billet overflow tank.
of course the Rat-Rodders like to use recycled soda, beer, etc., containers.
Coolant recovery systems on vehicles became a standard item in the mid to late '60's,
just as coolant in lieu of water had become a standard practice in the late 50's, early 60's.