OK - here's the big question: My '02 XR100 was flogged by the previous owner(s) and needs freshening up. The budget isn't huge, so am I better served by a TB or BBR big bore kit vs putting one of the Lifan motors into the XR frame? I'm pretty handy but not interested in a big frame cutting project. I searched but haven't been able to find any conclusive info on what's involved in fitting one of these motors into the XR frame. Has anybody done this?