1971 Scamp limited....

Actually, how it works is the radial welds will actually shrink the sleeve and break it free of any sealant, rust, etc. in the hole. Use a mig welder and go fairly fast, the idea is to get the heat in there and not weld it to the inner part!
Wait for a couple of minutes after welding and it taps right out using the little nubs tacked in there.
At least that's what Tom told me. What an intelligent man he is.
I'm just the official photographer here.