One problem that's likely to crop up is clearance over the brake drums at the rear. Multi-piece wheels have an almost straight barrel section, while single piece wheels need a drop center to allow a tubeless tire to be rolled onto the rim. That drop center sometimes doesn't play well with big brake drums.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!