9spd freewheel on 5spd hub

hi. i've got an old bike and it has 15 gears (hyperglide on the rear). i want to add more. appart from the shifter and the rear derailleur (spelt right?) i also need the rear cassette (freewheel).

will it fit on my hub? or will it stick out too much? apparently teh 9spd takes the same space as the 8spd becuase the spacers are smaller but does an 8spd fit on a 5spd?

if not, is it easy to build a wheel? i've read a guide on it but i'm hoping i can just take it to a local bike shop to do the truing etc.

 

No, 5 speed hubs are narrower.

http://www.sheldonbrown.com/gloss_sp-ss.html

If it's five speeds, I suppose it's probably steel. There are instructions on the web for bending steel chain/seatstays to fit newer hubs, but I have don't know where (Google time).