check out paeco. If you send them a stock one they can make a custom Copper Head Gasket for you. about 190 bucks.
I've used their stuff on prior cars and it's GREAT quality! i think i paid around 200 bucks with shipping for a copper head gasket from them IF my memory serves me right.
Also look into stronger rods and pistons as well if you plan on large Tq and HP numbers.
www.paeco.com
VERY nice guys to work with and deal with. I HIGHLY recommend them.
can't forget the fuel system as was mentioned before.
Eh.. i see I'm late, I've been beaten to saying everything from O-ringing the head to engine internals and fuel system upgrades.
As for felpro i've had good luck with them, but by the same token I've had VERY good luck with paeco. I guess it's six to one a half dozen to the other.