Originally posted by staleg
If I use a short waterpump and place the engine app 1 7/8" further back than stock CE position, it will be app 3/4" of clearance between the fan and the nose on the waterpump.
If you're going to do that I'd suggest not using the stock HEI distributor because you'll have clearance issues there. You can get a variety of electronic distributors with the smaller diameter head that will work as well.

Also, you may want to mock it up before welding and check your steering column clearance to the exhaust manifolds/headers. The further back the engine, the more chance of interference where they would "normally" come through the firewall.