To remove the old cam, you have to remove the timing cover, the distributor, intake manifold and the valve covers. The distributor/oil pump drive comes up and out. Remove the rocker shafts, then the pushrods. Next pull the lifters. The timing chain and gears come off, then you pull the cam retainer plate and slide the old cam out.
You may be fully aware of the following, but I feel the need to pass the info along: USE PLENTY OF CAM LUBE during assembly. ALWAYS use new lifters on a new cam unless you are using roller lifters. USE proper oil with a high content of ZINC. Test your distributor for spark before trying to start engine. This is easily done: with the distributor out of the engine, Attach one spark plug wire to a spare spark plug NOT in the engine. Turn the ignition switch to RUN. spin the distributor shaft and watch for spark at the plug. If you get a ZAP, you should be good to go.
It is extremely important for the engine to start immediately. The cam lube gets worn off of the lobes and lifters in as little as 5 revolutions! From there it is metal to metal and the cam and lifters can fail soon thereafter.
Good luck.