Before I drilled the holes for that pickguard, I strung it with a high and low E to ensure everything was suitably aligned. It was all good, but I found something else: the action was about 10 miles high. Higher than it should have been. So I pulled the neck to inspect the pocket a little closer and found, you'll never believe it: an accumulation of finish along the lip.
I got busy with some self-adhesive sandpaper and a machinists rule and within a few minutes I was looking at:
MUCH better. I added a bit of a shim, as there will be no avoiding it with this setup, and everything is better. It's still a bit high, but I'll worry about tweaking it when the correct neck is in position.
Final (I hope) wire up:
I put a full set of strings on it, and dang if it doesn't look VERY guitar-like!
The scale is all wrong of course, but I "tuned" it and plugged it in and made enough noise to verify my wiring was properly functional and, very thankfully, it checks out beautifully. The trem needs some adjustment as, at tension, it is all the way forward. You have two adjustments available to balance the leverages: the height of the stop bar and the position of the trem spring on the post. It'll take some trial-and error I reckon, but again, not going to fret about it till the correct neck is in place. I de-tuned it until the trem was in the middle of it's travel and will leave it that way to allow the springs to "settle in".