| Ben, I'm with you here-and since I'm always trying to come up with good-but-cheap approaches, I think you could do this easily without messing with the MM and it's rather high value.
The bass you are thinking about is the Jay Turser MM copy. I haven't played one but even if I did YMMV. If you get it from ebay, you would likely pay about $200 with shipping for a new one. I would definitely recommend getting the version with the all maple neck. This will sound great with slap. Then, doing it right, it will take another $100 to upgrade the bridge and the tuners. It will run another $100 for a good pup. That puts you at $400. Still that's about half of a real MM but I understand youthful impatience! At this point you should have a really fine playing bass. You will also learn a bit about working on them and you will explore some different combinations than you could normally. That, IMO, is worth the money and effort.
I would leave the real MM stuff alone until you can afford to buy a complete bass and keep it as such. It seems that the bodies and necks, as seperate pieces, go for pretty good sums. That would mean that you could do what I've described above for the cost of just a MM body and neck alone. | 
