Thanks for all the help guys! Of course I have absolutely no idea what I want at the moment in terms of the mechanical side of things. I imagine that a brand spanking new fuel injected 5.7l V8 would be easier to source, maintain and fit than an original (or as close as) engine which would no doubt require a rebuild - which isn't necessarily a bad thing I know, but its something I'd rather do myself and at this point in time, I think I'd rather build a car, and then once thats done, the next project can be an engine rebuild. That was a long sentence with too many commas.
The other thing to consider with engine choice seems to be what you're allowed to put in these things. Can anyone shed some light on the.... limitations, emissions wise? I know I'm thinking too far ahead here, but I guess my chassis choice will have to influenced by the engine I'm going to be putting in.
Which reminds me of another question. Years ago someone told me that side mounted/side exit exhaust were illegal to run on a road going car? Is this true, because I've seen a few of you using such a system which is making me think that the person I listened to years ago definetly won't be helping me out anytime soon with this project!