Rabbitoh,
There is a proper hub cap removing tool for use with dress rims. People like Slim sell them (or at peast reproductions of same).
I went to a large wrecking yard and whilst perambulating through the place (never know what you'll find
) I found that AP6 & VC Valiants have a similar tool, much larger (heavier duty) than the GM-H part.
What do they look like? Picture your standard hubcap lever with a second 90 degree crank in it. I'd reckon that someone else has a picture of one to fit.
Cheers
Brett
PS: 4hammers' solution is good though. Rob, in keeping with your name, do you have one for each wheel?