Yes, the controller is below the lower battery rest pad. You remove three small phillips screws (a jeweler's screwdriver is helpful). Remove the lower pad and the long wire cover; don't need to remove the upper pad, just the screw. One connector (w/red, yellow & black wires) must be disconnected to get the controller out. Then swap wires/connectors over. Use care to match the wires exactly. My bike had one red/black connector on the controller not used. There were two gray/black connectors, both going to sheathed wires on the bike. I tried to match them with the way they were originally oriented; not sure it would matter?Where does that fit in the bike? I assume it is inside the down tube. Is that easily accessible?
Anyway, everything still works! I put a couple of zip-ties around the wires coming down the tube to keep them in place better.
Here's some pics: