weld on ductile??

ok so i have a manual thumb on my ductile stick
it keeps on shifting upward then i cant line up the hole on the bracket .

how can i fix it from moving i got the nuts down tight even broke two wrenches in the process

the botom bracket slides about 3/4 over to the left . i got i back once with the help of a 5 lb persuader .

its like that bottom plate dont want to stay put . guess the bolt stretches just enuff to shift it when i grab rocks or logs

the plates even bending at the bolt holes

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weld on ductile??