What about a plate that picks up all three bosses with an extra hole that you can nut and bolt the rack strut to? That would be spreading the weight of the rack through all three bosses on each side.
Similar to what @Josh has said, but different
@user68025 started
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What about a plate that picks up all three bosses with an extra hole that you can nut and bolt the rack strut to? That would be spreading the weight of the rack through all three bosses on each side.
Similar to what @Josh has said, but different