Any shop that will take on the job of modifying wheels like that probably won't have the liability insurance coverage to address the disastrous consequences when (not if) they fail and cause an accident. I've modified a pretty good sized truckload of wheels for dirt track racing, but the US treasury can't print enough money to make me put one on on a street machine. The guys on the track are aware of the risks of running modified stuff, and they take them willingly. The soccer mom with a minivan full of kids didn't sign on to the challenge of sharing the road with some hotrodder's cobbled-up deathtrap.

Weld-modified wheels have a habit of developing stress cracks at the welds, as several stovebolters have discovered over a lot of years. One huge problem you're going to encounter is the fact that the drop center tubeless wheels won't clear those big brake drums. Tube type wheels have an almost straight center section that just barely clears the drums on the inboard dual. The cost of buying a properly made 22.5" wheel with the right lug bolt pattern is cheap insurance, considering the possible consequences of running something that's ben modified.
Jerry

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