That looks like the classic rubber bumper end internal frame transferred rust. How were the condition of those frames on yours? I really hate how they nearly universally kill the fenders right at the bolt hole. When I get around to this, I'm thinking of spacing out the frame with a bunch of nylon washers and perhaps even using a plastic form of attachment, anything to keep the same problem from happening again and again, though you going to the euro bumpers will probably work just as well!

This thing is really coming together! Looking forward to completed fender pics, are you having them do a racing stripe?

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