I'll never run ethanol or e85, that shit is nasty. Stock internals will easily outlast the stock block, up till 93 foxes came stock with trw forged pistons so as long as you have a safe tune those will be fine. The block tends to split in the 450+ range and the pistons, rods and cranks are good for at least 550, I wont run meth since that stuff is highly corrosive as well. A little bitty 302 with decent heads and 10psi with a good flowing intake and some sort of charge cooler will easily make 500rwhp, pass smog and you can keep the a/c unlike the turbo kits for foxes.
As far as tuning it will easily run on 91 octane.
My advice is to buy one of the rollers on the
www.corral.net, you'll generally find ones that are substantially modified less a heart and will/can be purchased for around .30c on the dollar and will be in great shape.