Ive read 1 gen fbody can use a new aftermarket Holley oil pan...also a 4th gen fbody oil pan will fit but need to be modifed (street & performance can do this...
http://www.hotrodlane.cc/ ). Not sure if vette batwing pan will fit.
having the vette accessories is a plus...most people run into issues with the fbody or gto accessories hitting steering components.
fuel system. before you buy tanks inc, read up on the vetteworks swap (
http://vetteworksonline.net/ go to the engine conversion section). It's a 4th gen fuel pump, built in return line and pressure regulator, drops into your OEM tank. tank height is the biggest issue. There are other fuel buckets (shorter) than can be swapped in. I think the 4th gen bucket is a much better way to go than the tanks inc. I did the vetteworks swap...love it..no issues and well under $500.
you could do a head swap and possibly put a new " no return" fuel rail system in
hop on and join "ls1tech. com",
http://ls1tech.com/forums/conversions-hybrids-28/
lots of other people have done the LS swap into 1st Gen!
good luck and welcome!!
good book-
http://www.amazon.com/LS-Series-Engi.../dp/1932494812
Leon