Never knew it would be so difficult to fit a baby moon on a basic nub style steel wheel without damaging the hubcap. Found a pristine set of what I call bowtie baby moons, aka poverty caps from the late 60's early 70's that I think look awesome on an AD truck. Fortunately, I first bought a cheap set of generic chrome plated caps to ruin/learn on.

You don't just thin the lip where it fits the nub. To make a long story short, the entire lip needed to be narrowed by a teeny weeny bit. Maybe 1/32 or 1/16 inch all the way around. Vise grips can be set to give a uniform crimp and I eventually solved the problems of leaving external crimp marks by chucking the vise grips in a vise and covering with masking tape.  Process is not as slow as you'd think. Benefit is stretching the cap uniformly around its edge without turning the round cap into something resembling a football.
on the truck 1
on the truck 2
 

Matthew 6:33

1952 Chevy 1/2-ton 3100
Late '55 235/SM420/torque tube 3.55
Dalton Highway survivor (using original 216)
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