Would this work?

If I were to make the neck joint on the body bigger?

Or is it a lot more complicated then I think?
Quote by Explorerbuilder
You would have to completely rebuild the body. Not worth it. The pickup cavities, neck pocket and bridge holes/rout would need to be altered.

This. You'd have to expand everything yourself to make the parts fit
part of it is dependent on what kind of guitar also, if it is a floyd, or a hard tail, or a tune o matic. Some types of bridges work better for this. changing the pickup cavities is actually the easiest part, get the neck pocket to be the perfect size, and having the bridge line up perfectly is the hard part.
However though if you want a fun project it could rule!
Well the thing is,

I have this cheap explorer shape body lying around
for wich I still have to make a neck.
And I just thought why not make it a 7 string.

I already have to repaint the body so changing the pick up cavities isn't going to be that dramatic
and i was thinking of making it a string through body
well you could extend the neck into the neck pickup cavity to make up for the lack of support on the original pocket.
Bassist/Vocalist-Visceral Violation
Mesa-Boogie Big Block 750/SWR Megoliath
Warwick Corvette
Seriously. Has no-one listened to me!? This is NOT going to save you any money on buying a 7 string guitar or anything like that! All you will end up with is a crap guitar that you will have spent so much money on that you will have been able to easly get a budget 7 string guitar. If you are desperate for a 7 string, sell the guitar you have now and use the money you would have bought a neck with to get yourself a 7 string. I bought a shecter omen extreme 7 string. Great guitar, and less than £200.

"Show me war; show me pestilence; show me the blood-red hands of retribution..."