I am a GM technician and Machinist. Go to a parts store and purchase a motors manual for Your car.The install is the reversal of the removal. Get the head set and make sure they are for a 454. Install the heads and torque the bolts according to the manuals specs. After cleaning the rockers and push rods install them. There are 2 different size push rods. You have to adjust the rockers at top dead center for each cylinder. Turn the nuts until the push rod stops turning, then 1 complete turn. Read the manual so it is not done wrong. Adjustment can be done with the engine running, clips on the rockers, back off till rockers clatter and then tighten until quiet, then 1 turn. Google on the computer can look up Your information if You ask for it. It is not easy work but I have done many. Let Me know what vehicle You have and any more help You need. NICK L72