Bore depends on the block; you will have to sonic test to see how far you can go. Some blocks can only go .030 or .060...others can go .120. Here's proof:
http://misn.com/~frd460/blocksummit.html
Stroke up to 4.5" can be done on a production block without a problem. There are FORGED 4.5" stroke cranks out now...by the way. No need to use a cast part.
Personally, I'd use a D9TE block (longer bores, better piston stability) and a forged 4.5" crank on a production block converted to blue-thunder billet splayed 4-bolt caps on 2,3,4. A good H-beam rod. Good Forged pistons. Screw-in freeze plugs. Fill the block to the middle of the freeze plug holes with devcon or hard-blok. You now have a bottom end capable of 1000+hp before failure.
I'd also spend time on
www.460ford.com and read through all the engine tech stuff...there is a lot of REAL knowledge on there from people abusing these engines to the limit.
Byron