I'd think that an offset rather than a right angle flange would work better. Eastwood also has tools for forming an offset.
Pneumatic Flanger
Hand Flanger
Wide Hand Panel Flanger


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.