Today I did a mock up with the Peerless Gear differential, yet another 60T sprocket mounted on the LH side, and another 8" steel rotor on the RH side; a little mechanical caliper can mount right under it on currently non existent mounting bracket. This drive train revision leaves no clearance for the stock trunk. I haven't decided whether to go with a foot or hand activated rear brake.
Differential sits all the way on the left because of the drive sprocket and chain position. LH axle half will be stubby after I cut it to size. Unforfunately, the RH half isn't long enough to mount my wheel & hub.