Well,
I was actually able to reach the truss rod nuts quite nicely with a small 1/4" open end wrench. The neck straightened up nicely, I lightly shaved down the top of the frets and redressed them. The nut didn't need any filing at all, the grooves are just the right depth. Now tonight if the neck is still where it should be I'll replace the strings and set the action and intonation.
I then have to replace the input jack. Thankfully I have one of those type of jacks laying around already, and a stereo one two, whew!
In working with this thing, it seems to me that the neck is very, VERY dry. It almost feels like bare wood that was never finished, but I'm assuming at one point it had a thin coat of tung oil or something similar on it. This could easily contribute to the neck not being stable. I have highly recommended to the owner that we get a few good coats of tung oil on the neck, and that seeing as the climate here is high desert with the humidity usually below 30% and often into the middle teen percentages, I've advised him that a new coat of tung oil and/or warwick wax should be put on it once a year.
All in all, it's not a bad little bass, but I find it to be about the same as the new Toby Pro's from Korea. Granted, the electronics on this one might be a bit "better", but the overall feel, fit and finish gives off a "$500-Guitar-Center-Mass-Produced" vibe.
The current Bartolini catalog shows the "MM" pickup as available, but only in a dual coil, not a quad coil.
:^)~