Mr. Hall,
I recently purchased a blacked out 78 azureglo 4001. Having found this thread, I disassembled it to see what I could see. The pickguard is black plastic but looks sprayed underneath, the TR cover looks like black plastic, but has some black spray on the back, as well as a finger print, the black hardware has rubbed off areas showing chrome, sometimes onto the blue, and the odd fingerprint (no discernible print, just recognizable as a fingertip), so I wondered if this could be one of yours? Wasn't sure how careful your spraying would be if it was a rare one off request, no booth, no instruments to hold the pieces, etc. The other interesting thing is, there are small amounts of blue paint on one tuning peg and on one piece of hardware, but under black light, the bass was never touched up with blue, unless it was very early on, and with the exact blue. The letters on the TR cover are blue, one the black, and very well done, if an amateur was doing it, they for sure would have messed that up, that blue has a different look under black light, but that may be the case as it's on plastic.
So, here are some pictures, love a good mystery

love solving them even more!
https://imgur.com/gallery/GgvD9D0Thanks!
Hal Cooper