Camshaft Installation and Degreeing Procedure

Camshaft Installation
Step 1: Prepare a clean work area and assemble the tools needed for the camshaft installation. It is suggested to use an automotive manual to help determine which items must be removed from the engine in order to expose the timing chain, lifters and camshaft. A good, complete automotive manual will save time and frustration during the installation.
Step 2: Once the camshaft, lifters, and timing chain are exposed, line up the timing marks on the timing gears by rotating the crankshaft (fig. A.). This will position the #1 piston at top dead center. Next remove the camshaft timing chain sprocket, the timing chain and the camshaft retaining plate if equipped. Remove all lifters and reinstall the cam sprocket to serve as a handle. Slowly and carefully “roll” the camshaft from the engine. Note: Excessive force is not required to remove a camshaft. If the camshaft does not come out easily, stop! Look for obstructions, such as a fuel pump rod, distributor gear, etc. Do not force the camshaft; something is holding it in the block.
Step 3: Once the camshaft is removed, pull the bottom timing gear off of the crankshaft snout. In many cases you will need a gear puller to remove the crank sprocket. It usually has an interference fit, which may make it difficult to remove without the proper tool. Be careful not to damage the threads in the end of the crankshaft.

Source