870 factory mag extension repair

[Romulus]

I got a small dent in one of these up by the mag clamp, on the short section forward of that funky groove that these mag extensions have. This means that I cannot drive a socket from the open end to iron out the dent, as the socket cannot be driven past the groove. I thought of heating up the tip, and debraze the cap. Then insert the socket through the front to iron out the dent. Then I would have to rebraze the cap on.

Anyone here have experience with repairing these items?

Thank you in advance