Radiator, no overflow tube

[izze]

I've been working on my vehicle over the last few months. Fixing things here and there. The engine runs a little better after each repair. And with each repair, I drive the car a little more. And with each drive, the engine will overheat sooner then the last drive.

I tore apart the cooling system. And I found that the gooseneck is in pretty bad shape. After draining the system, I found a lot of junk sitting atop the tubes in the radiator. (2 tube core) I replaced the gooseneck. I back flushed the engine. Back flushed the radiator. I let the radiator sit in vinegar for a few days, and continued to backflush it once a day. Now the tubes look really clean. And when I get the system put back together, I'll run it with vinegar for a week or so. Continuing to flush as I go.

I'll check timing. Re calibration the carb mixture. Verify the correct coolant level, etc.

So, the radiator makes a hellova mess every time it overheats. Boiling over at the cap, and draining all over the front end. I thought I would take a look at the overflow tube when I took the engine apart only to find that there is no overflow tube. I have 3' of 1/4" brass tubing. And I feel like it would be really easy to drill a hole into the radiator top reservoir, and weld in the tubing to make my own overflow.

Any advice on adding in this tube?

And is it common to find no overflow on these older radiators?