I am fixin to replace the Vortec 5 liter in my '99 extended cab(old body style). Have'nt got the new motor yet. Probably going with a crate replacement. This is going to be my first Vortec truck swap. What am I in for?????

Welcome to AF, have you changed an engine in any vehicle, your question is too general. We could post 10 pages of instructions if you are new at this.

Oh yeah. Changed several engines out. From front drivers to TPI's. All I've ever done to a vortec is change oil, belts and water pumps. PLan on getting a crate motor and using the induction, exhaust and other ancilleries off of the kaput 5 liter.

No big deal you are ready to roll, premium gaskets of course the usual break in techniques, careful removing and reinstalling sensor conectors.