The wood shim and plastic C-clamp wasn't holding the rivets in as well as I'd like, so tonight I came up with another solution.
I had an off-brand name vise grip clamp that I cut apart, and welded the feet to another clamp.
Then I welded a little nut on the opposing foot. I chamfered the inside of the nut to better fit the rivet heads.
The 3-finger clamp snugs the heads tight, holds them and gives me room to weld.
Thanx for the idea.... I have had a Vise-Grip "C" clamp with one leg broken off kicking around for years, waiting to be made into something special..... This looks like a great idea.... Thank you

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