Neck thru or Bolt-on?

If it's bolt-on, Carvin probably still can sell you a neck that would fit your bass (they make great kits for their guitars - you probably already know that). If not, then shop for a luthier.

If you can't make headway with Carvin (which I doubt - fine company) then I would ask for a luthier on the fenderforum - where there are boatloads more guitarists and luthiers on hand. www.fenderforum.com and navigate to one of the the repair sections.

No harm in going there with your Carvin - it's not an official forum for Fender. Lot's of folks there have products other than Fender.

Another place would be the TalkBass forum. http://www.talkbass.com/

I would be too nervous to remove the fretboard. At least

Good luck oh ambitious one!

Edit: just googled - neck thru. Luthier it is if it was me (I forgot to vote)