Hopefully the one you bought will be "clocked" the same as the one you take out. I think most are the same and its just a remove and replace. Its safer to set your engine to Top Dead Center before pulling your old distributor, then when you sit the new one down, it should either sit down at #1 or #6 plug wire. If it doesn't point to either #1 or #6 then come back and let us know!!!
There are a couple of ways to find TDC. Search the threads for top dead center. I use a piston stop, but you can also use your finger over the #1 plug hold and feel for compression while turning over by hand.