How would you go about doing this? Is the fretboard glued on or what? How do you put in the frets and trussrod? How would you put in the truss rod in a fretless maple with no seperate fingerboard? Any special saws to cut the contor of the neck? Thanks.

your best bet is going to be reviewing the Sticky at the top of this forum. Look for the section on building books and select one or two from the list.

Once you have these in-hand, read ... re-read ... re-read ... re-read ... re-read ... re-read ... re-read ... and re-read once again until you feel ready to take a stab on a prototype with some inexpensive wood.

all the best,

R

FWIW, it is easier, a better learning experience, and more fun to just build yourself an instrument from scratch than to heavily modify an existing one.

And then of course, you have yourself another bass!