Yeah, I'm over 3,000 miles now on that bike... No problems at all, oil-changes every 25 operating hours (50 is recommended) and a valve re-lashing to help the altitude issue. My rear-axle is starting to get hot around 3hrs of continuous riding, I notice the drag in the downhills.
Thanks for the compliments, I enjoy the **** out of it... Rode it through 5-inches of snow during the storm; a few times.
Maybe you could use the t-belt system for your swap? It would definitely let you use a sub 2" pulley and the belt might be able to hold up well enough. Not exactly cheap either though... maybe swap with alternator pulley -> Power Steering pulley -> alternator pulley? Great availability in belt sizes for the V-belts so you could try different configurations too.
Good luck man; I have no clue how to mount them to the shafts...