Jumping back here from Mohawk's 5th Gen single-nut topic.
Around April this year I decided to get serious about my own 848 wheel mod - I'd had all the parts sitting around for two years or so, as is usual with me. I took the 848 rim, an aftermarket aluminium one-piece 848 wheel nut, the Triumph spindle and my single sided swingarm stand pin down to my machinist and for $60 he cut down and re-threaded the spindle to take the wheel and nut (he's a bike guy himself), and turned down the stand pin so it would fit nicely into the spindle.
Then took it all home and bolted it together. Result:
I haven't fitted the Triumph rear brake bracket, or checked the chain alignment, so that is next. Might need to make spacers etc. as you've been doing.