The factory service manual (FSM) and cuda-challenger.com
There are several restoration books for E-bodies out there, and all of them contain errors (I have one by Paul Herd, called 'Challenger and Barracuda Restoration Guide'). Depending on how 'correct' you want to do your restoration, they may be OK...You mentioned possibly using a 5.7, so I assume this is not a 'numbers' resto.
But you will find yourself using the FSM more than any of them. And you're fortunate to have found this site before starting - The helpful folks around here are a wealth of information!
-Tom