Personally I'd cut out the factory mounts or build around them. If you learn how to use a welder and fabricate it doesn't look too difficult. I was examining my frame because these machines are famous for doing this. If I ever have any issues with mine, I will run a brace across the bottom of the frame from one peg to the other and completely re-fabricate the mounting points. If you're not capable of fixing it yourself, find a local welder to help you. In the hands of a skilled fabricator, it will be an easy fix and you won't need a new frame or even new pegs more than likely.
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