Ran into a few more hiccups.
The nut I bought was too low. Thankfully Graphtech does free exchanges, so I'll be swapping it for a taller one - albeit with a 9.5" radius, which I'm not really concerned about.
The bigger hiccup is the electronics. Individually the components seemed to work as I hoped, but for whatever reason when wired up I could not get sound out of the neck pickup. After checking and rechecking and rechecking again I just ripped it out and I'm going to try an alternate configuration.
Instead of using a dual-gang pot and a standard 5-way switch, I'm going to use a standard 250k pot and a 5-way super switch. I've never mucked with a super switch before and it's kind of annoying, because with a standard switch I could get the neck and middle on their own pot quite easily on the two poles... but that would chop out the auto-split. And with the super switch, I need to use two poles just to get the standard 5-position Strat wiring, and with the splits taking up an additional pole I have just one extra pole to make it all work. And even then I had to compromise a bit. And even that is assuming it will even work....
So here's what I came up with:
Red: Neck hot
Yellow: Middle hot
Blue: Bridge hot (output of 500K pot)
Purple: 250k pot
Poles #1 and #3 go to the input of the 250k pot. In position 2 the bridge pickup goes through it as well. The bridge pickup goes right into a 500k pot before hitting the switch. Pole #2 goes to the jack, and in positions 2-5 it gets fed the output of the 250k pot, while in position one it just gets the bridge pickup. Pole #4 splits the pickups in Positions 2 and 4 and outputs to ground.
If this doesn't work it's back to square one.
However, I was able to pluck a note out of it on Halloween as I'd hoped.... so that's the official birthday of this Monster.
Maybe not so successful as that (if you can consider killing a hunchback and drowning a child a success, which I certainly do)....
That's more like it.