I purchased a Rivnut gun yesterday at Parkrose Hardware. That place is amazing; they had all the hardware and rivnuts I needed. It's associated with TrueValue hardware, so people in other areas might be able to go to TrueValue.
Here's the Rivnut Gun. It's expensive($65), but I suspect it's easier to use than the tool shown in the VoltsPorsche DC manual. I didn't receive any rivnuts or tools from ElectroAuto, so (in my impatience) I just went out and got my own.
Tonight's project was installing the potbox that I assembled a few days ago. This requires taking out the cabin seats and pulling the upholstery behind the seats forward so you can access the bolt heads as they come through the wall.
Here are the two upper bolts from the potbox coming through the firewall. The bottom two are installed with rivnuts so we don't see them. I have a friend coming over tomorrow to help me attach the nylock nuts. The directions say to install the bolts from the passenger compartment side, but I found it was easier to push the bolts through this way.
Getting the bolts to line up properly on the firewall was difficult due to the rust and grime on the bottom edge that screwed up the alignment. If you go too high, you bump into the brake cylinder(see picture below). If you go too low, the bolts don't come through at a flat place in the firewall (see rightmost bolt in above picture). Furthermore, if you purchase spacers, make sure the 1/4" bolts actually go through the spacers. I spent an hour filing out the centers of the spacers so the bolts would go through (argh!).
Here's the potbox installed. I still need to add the spring, cotter-pin and 5mm threaded barrel listed in the instructions, so I hope those come later with the remainder of the kit parts. The grey wire coiled off to the left will install onto a terminal block soon.
Electro Auto shipped their first AC wiring harness to the first AC kit customer and it arrived today. I'm excited to get my own terminal blocks, relays and harness soon.