I have the tdr mount & single speed hub. Right now I have the stock spur (can't remember the size) and a 22t rcm pinion. I haven't run it like this yet, but it looks like it's possible (maybe only just). I believe the max spur size is 66t. So with 22/66 gearing you'll have plenty of power.

When I built my roller I bought a new afterschock tranny because it comes with the foc installed. I believe I got this tip from linc's LST conversion thread.