KZ 900/1000 wheel conversion?

A friend is acquiring a pair of cast KZ wheels complete with rotors (2 front, 1 rear) Pretty sure this is an 19" and 18" front and rear combo. If I remember correctly, the rear 18 uses a 4.00 tire, so there shouldn't be clearance issues, but not sure if the front twin discs would fit a Roadholder fork. Just wondering if anyone had considered this combo for conversion?

The out-to-out measurement on the rear KZ, sprocket-to-rotor is approx 7 1/4". My MkIII rear setup is around 7". So depending on offset, seems doable with minor adjustment of either the rotor, the sprocket or both.

On the front, the KZ dual rotor width is 4 1/2" out-to-out. Roadholders have 5 1/2" between with the single rotor only an rch away rom one side. Also sounds doable. Speedo drive is on the front.

Back in the eighties I put a set of Yamaha wheels on my 850. The front, from an RD400 was a simple bolt on, only needing spacers made up as the bearings were the same size as the Norton. The rear, from an SR 500 with cush drive, required machining of the wheel to make it narrower at the sprocket carrier to align the chain. I don't remember the specifics as it was a long time ago but I am still using the same set up with no problems.

I hae heard of that conversion using Yamaha XS 500 wheels. Probably pretty similar. My buddy hasn't decided if he wants to convert his old, wire-spoked, rear drum Z-1 to cast wheels and dual front/single rear disc.