Use a bottoming tap if available to clean up these threads . Use new fasteners w/anti-seize so you will not have this trouble again. On the holes with damaged threads you can install studs on these holes.* Make it look good and put studs opposite of these to give it symmetry . You can make your own studs w/threaded rod. It is cheaper in the long run . Used flanged nus & capscrews too !
* The reason being , you will be pulling on these threads rather than turning/twisting of a capscrew .
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