custom sub boxes?

has anybody built there own sub box for there 3rd gen , ive been reading up on fiberglassing but i was wondering if anybody here has done it ? if so can you offer any advice i might need?

Ive built my own sub boxs for them.. A couple guys here wanted the specs, im workin on it right now but it is a complicated box to explain in ms Paint..lol.. But I dont have a digital camara
I can send em' to you when Im all done.. see if you can make any sense of it if ya like