I already have the conversion kit based around a mountain bike with a wheel size maximum of 26 x 2.3 width tire.
The battery I originally ordered was a massive 52v 20ah. It was designed to fit perfectly on the down tube with very little room left. The listing showed there were only 9 left so I quickly ordered and paid for it. The seller contacted me the next day and claimed there was no inventory left (although the listing now shows 8 left) and offered an upgrade to a 52v 22ah battery for an extra $20. That was worth it, I figured.
What I didn't count on was the changed dimensions. The 52v 22ah is longer and higher ... it just won't fit in the space of the full suspension donor mountain bike (or any part of it, and a rear rack is out of the question). So, I had to go to plan B ... a front suspension mountain bike with hardtail. Would be a bit of a rougher ride, but the front suspension is a high end unit and I think I can make this work. The down tube, top tube, and seat tube geometry is excellent for an ebike build. Lots of space for the battery and controller.
A new glitch ... let me explain. This CCM Incline hardtail was damaged during riding. It belonged one oldest grandson, youngest grandson was using it at the time. The rear wheel was damaged and came off. As the frame came to rest on the road, the rear Shimano Altus derailler was damaged and so was the chain. What I didn't initially notice is that the derailler hanger was broken off. Part stayed with the frame, part stayed with the derailler. The only good thing about this is that the hanger is a replaceable unit (see at right) ... I just have to find the right part and resume the build. A part is on order from Amazon.