I really liked the previous location under the tank. Because it was toward the rear of the steel tank, it shielded the rider from a meltdown. So my plan is basically put it in the same place, but a little higher to clear the battery tray fasteners.
I found a cool piece of 3/8" thick acrylic in a salvage pile. It had several holes cut into it, probably to hold or display something. Perfect for mounting the electrical components, however, not strong enough to hold the controller. But it was so cool looking, so I had to use it.
I trimmed the Acrylic to fit the front 3/4 of the frame opening. Conveniently a couple of threaded inserts were already located on the front edge (formerly for some rubber pads to support the tank). I drilled and tapped a few more spots on the frame rail to finish securing the piece.
I trimmed a scrap of 3/8" aluminum plate(leftover from my motor mounts) to span the frame rails and support the controller. Some creative filing and grinding was required to work around the welds. A few drilled and tapped holes later, the controller is mounted.
I even had a little time to mount the Contactor and do a little wiring. The precharge resistor and main fuse are mounted directly to the contactor. Color coding the high-current wires (#2 gauge welding cable), keeps me from getting my wires crossed.
NOTE: much of this wiring layout is only temporary to shakedown the powertrain.