I agree with Clifford . I've seen this done several times the bolts will break often if there's moment or expansion type stresses. If welded less through and behind a plate work better. The bolt with no shank/full threads doesn't help. Heavy nuts welded behind a plate will strip more easily but hold up much better.
If using a threaded plate it looks like there's room for a jamb nut to keep a stud locked in. I would try a case hardened stud if you can find one to use with the plate.
95 Monaco Crown Royale
M11 400hp, 4060 trans.
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