Hi...can you tell me how old it is? Also are there's any serial numbers on the back? From what I can see in the picture, it looks like the pickups are not the stock one (either MIJ or MIK)- they're EMGs? (can't quite read it). I'm inclined to say it's a Korean one as it looks "newer" than most of the MIJ ones I've seen. It also has 5 knobs instead of the 4 you typically see in most Maniac models MIJ. Speaking of knobs, if the ones on there are the original ones, they look different from the knobs the MIJ Maniacs usually have.
Fretboards on the TWB basses- on the Korean they're rosewood, on the MIJ, they're ebony. I don't think this holds true for the Maniac model as I've seen MIJ Maniac basses that look like they have rosewood fretboards- so sadly, I don't think we can use that to determine the country of origin.
Any info on the back if any would help to identify the country of origin. If the serial number starts with "s" followed by the year, it's Korean.
Also can you tell me the make or stamp on the back of the tuners? That should also help.
Regardless, that's one beautiful bass you have. Congrats!