Are you attaching the sprocket to the axle hub or shaft? I've been thinking about doing this for a couple years too but the shift linkage is in the way on one side and while the other side is doable if I went to manual brakes, something I was planning on doing anyway, it's right next to the exhaust manifold which probably would require a heat shield and funky electric motor mount. My pickup would be easier since I could just shorten the driveshaft and put a double shaft motor inline, but since it has to be smogged I have to get it legal somehow and the PR person I talked to at CARB was a total bonehead.