I may be missing something, but are the four mounting bolts only threaded into the 1/2" plate of mild steel you welded to the frame? If thats all that the bolts thread into (from the picture of the tap) seems like not enough for the forces transfered through that steering box. Maybe you've added steel nuts from inside the frame rails, if not you probably should.
Otherwise looks like a good setup. I'd like to do a similar setup on mine some day

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