Freeze Plug Installation ?

Larry

The metal plugs are prone to rust if you don't keep rust inhibitor in the antifreeze. Permanent antifreeze doesn't mean forever. I usually change
it every other year.

When I was a kid my dad always used Zerone that was an alcohol antifreeze. Used it over winter and drained it in the spring. Never had any radiator clogging problems like they do now. When we got an H Farmall it had the Zerone too.
The 10-20 we had was always drained after use in the winter months and that radiator never leaked.
Hal

If the plug is disk style, it goes concave side in, after which you need to flatten the center 1/2 of the disk with a hammer - don't overdo it.

Larry

If it is just a "plug", install it with the bow out. When you have it correctly in place, smack 'er in the middle with a good sized drift to spread, lock, seat and seal the gizmo.

Allan

If the old ones were the "cup" type, I really wonder if the plugs will work.

The plug types need to rest up against a ridge in the bore. Cup types don't.

Allan