A very very poor attempt at answering your question. Hopefully it is enough to help a little.

Thoroughly check the condition of the engine and transmission before you begin.
Example:
The Borg Warner T-56 (1993-97)...good. Tremec T-56 (1997 later)...problematic. This is info gathered off the Internet whether true or not.
A built LS1? Engine rebuilt and HP parts added or original engine with HP parts added.
Your LS1 is fuel injected so there is a computer. How good are you at wiring?

Original truck rear axle width:
http://chevy.oldcarmanualproject.com/chevyresto/51054.htm
Since you have both axles available, you should measure yourself from backing plate to backing plate and compare.
Obviously the 2000 Camaro is not fitted for leaf springs.

Front axle maybe spindles with rotors and brake assembly can be reused.

The quickest and safest route is to buy a prefabricated frame-suspension-steering package designed for your truck.

"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."