I figured out how to mount the ATC90 footpegs. The two rear mounting points bolt to the engine plate mounting bolts through a steel adaptor plate. I had to re-drill this plate when I realized that the original ATC bolt holes were slightly offset to one side. At the front of the footpeg assembly, I had to relocate one of the bolt holes in order to clear an existing bolt head for one of the vertical engine plates. I drilled and tapped two holes in the bottom engine plate to accept 8mm helicoil inserts.
The ATC pegs are quite wide and don’t fold, but they’re high enough that they shouldn’t cause an issue with cornering clearance. Given the total lack of engineering that has gone into this configuration, I doubt I will be trying to drag my knee on this bike. On the plus side, they are wide enough to clear the CVT housing on the left and the recoil housing on the right. They might look odd, but they seem ergonomically right; I sat on the bike and my feet were right where they should be for my height. In fact, the bike feels as though it will be really comfortable overall.
The weather this morning was nice enough to roll the whole thing outside to record my progress over the winter.