Using MIG to repair old brazing work?

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Hello!  I found this forum using a quick google search, and i'm hoping someone will be kind enough to answer a quick question for me.I'm restoring an old motorcycle - a 1969 Rokon Trailbreaker.  Its a crazy 2WD beast of a thing (google it for some pictures).  Anyway, there has been a frame modification / repair that was less than ideal that I want to repair.  I'll post some pictures up.What it looks like is that the kickstand mount was relocated, and the framing tubing was chopped and then brazed back into place.  I've spent some time with a 60 grit flap wheel grinding down the sloppy work to get it to the point where I can start rebuilding.I have access to O/A torches, a MIG welding machine, and a ARC machine.  I've done a bit of MIG work - but I'm still very much an amateur.  My question is can I MIG over the previous brazing work?  Or do I need to grind it all off, chop it, and start fresh?  thanks in advance!here are the pictures - the red circles some some cracks / incomplete welding that needs to be fixed.  Two pictures are how I got it - the other two are after I started grinding it down.http://img24.imageshack.us/img24/9466/dscn0471b.jpghttp://img13.imageshack.us/img13/3889/dscn0470a.jpghttp://img715.imageshack.us/img715/7730/dscn0476a.jpghttp://img180.imageshack.us/img180/1590/dscn0473x.jpgLast edited by Fursphere; 04-01-2010 at 11:32 PM.
Reply:I think you will have to get rid of the brazing. I know I would. Some of the experts will post with their opinions. Good luck.
Reply:You cannot mig weld over braze. It must be ground off completely.
Reply:You have to get rid of the brass (bronze actually) before you can successfully weld it with any process.
Reply:Ditto on what has been said so far.Is that section suposed to be contoured or straight?  If straight, I would cut it out past the 'welds', replace it with a donor piece, cut the stand bracket off the old section, clean it up and weld it to the new section.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:There is a slight "S" bend to that section.  http://img180.imageshack.us/img180/6752/dscn0467n.jpgYou can see it in this pic a little.  So it looks like I'll be just removing the section and fabricating a new one.  I was wanted to repair it once the correct way, instead of doing it wrong, then redoing it later.  Thanks again!