You could get there with a TA block or an Off-center stage II block though they are both going to be expensive and good luck finding an Aluminum Stage II. The problem with getting 800hp out of either though is going to be running that much booste is going to run into detonation problems most likely so Alky on the street works for plenty of us though it your in the throttle all the time you'll drink it almost as fast as gas tank wise. What would be really cool is to get an all Aluminum DOHC 5.7L LT-5 Corvette ZR-1 V8 and its matching ZF 6-spped, and put that in there with some good tweaks that make it smog illegal if your chassis will let you get away with old emissions standards, maybe even turbo it. Else wise your pretty suck with with either just another small block or a new Gen III/IV (LS1/6 and LS2/7) which would also be insanely cool but again very pricing and a lot of custom work though your T-56 problems are moot.
As far as your all wheel drive, I don't think your going to do that with a stick unless you're looking at a foreign WRC type setup. Though Troy Trepanier did an AWD '32 Ford (Quadra-Duece) with a Sy/Ty (Syclone/Thypoon) differential and transfer case and a T56 but you know there is major custom work there. Also if you do that you will need a torsion bar or pushrod cantilever style front end to clear the CV shafts for the front wheels. You could also do the horrible early Ford style upper A-arm mounted springs and shocks but that doesn't play well with a low and narrow cowl line, also a McPherson strut style front end could be used but with the same issues since it would have to attach to the upper A-arm.
Just my mad musings.....
