Late to the party Doug...but yes, it is just that simple. Like replacing any other timing set, except you have the super-dee-duper technical task of lining up the notch with a dot on the crank to the corresponding notch/dot on the cam. If you've never swapped a timing set before, the old set usually needs some persuasion to come off...I just use pry bars against the block. Then sliding them on can get a bit frustrating if the gear and sprocket aren't aligned just right...then it won't want to slide on the crank snout and/or bolt up to the cam.
IMO...the only way to go are Cloyes double rollers. A little pricier, but I always end up ditching whatever 'I just threw on' later. I do have a few spare Comp double roller sets that came with cam kits, I'd like to try...but haven't needed to with Cloyes units installed/reused.
They both have the three keyways for retarded, 0, and advanced. The 3121 mentions a standard center distance, and the 1121 says nothing. Other than a slight change in description, they look exactly alike to me.
Also, what do I need for a gasket kit to do this job?
I would...just to get any crud out that happens to fall in. Chances are you'll have old gasket fall in anyway (I suppose you could drain the pan and weasel a shop vac in though), and when I start prying the timing set away from the block, I don't want to mangle the pan.
Thanks for the info, Ben. Ordered a timing set from Summit today. Since I don't have any room in the garage, this project will wait until winter is over, like July.
Make sure you're at TDC. You'll have 3 keyways (on the cam gear), so just make sure the dots line up on the gear and sprocket. You'll want the middle dot for straight up timing (others are 4* advanced or retarded). And then you'll want to throw a light on there just to make sure you're between 10-14*.