Cobra front end with SWB rear end.

http://imgbox.com/1LN3AeZT

That's rather nice.

That shouldn’t work, but it does.
Very nice!

Looks good from the front. I don't think it would look right from the back. It would be 250 SWB !

Looking at the original post and what's trying to be achieved I wonder if z4 coupe is better starting point. The bonnet/cabin/boot ratio is much better suited. Some of the wide body kits give an idea of how it may work.

The s4 panels don’t come off like a z3 do they ? but I agree better base shape