What if I where to take and cut the roof and side windows off around my cargo area. Then build a new rear firewall, can't really think of what to call it, then use the back defrost window from the hatch and put it directly behind the rear passengers heads. So it might look like a four door Brat with a very short bed.

 

Lots of work but has it been done before??

Yes has been done before. Search this site for pics. IMO when its done it looks horrible, But thats just my Opinion.

A proper ea82 brat will have the rump roast and top end of a 3door grafted to a wagon body, with the 3door b pillar and side sheet metal, the rear quarter cut out and the c pillar moved forward.

 

One could make a 2 door sedan if they romoved the tailgate from a 3door and grafted in a sedan c pillar, decklid and back window.

 

I dream of these things...