Small block engine won't start now need help!

Update: I just got finish retarding the distributor more and she did fire up. I think what happened yesterday was that I didn't feel like it would turn anymore, so I didn't want to do something I shouldn't. I looked at my #1 and #6 plugs location on the distributor cap and noticed that there was definitely some room for retarding the distributor more.

However, the car is idling rough. I will start over with the timing (in a day or two) to see if I can get it to more of what I had yesterday. I have some more questions however; 70aarcuda you mentioned to check the air gap which I think was done, but I probably will check it again do you know off hand what it should be? Daredevil in your statement are you saying the distributor is still bad even though it will start now? If so, please explain again if you don't mind. Now I want to make sure when I time it this time around I am getting the right readings for the engine. I know ideally total advance should be in the 36 btdc range, which takes in effect the initial timing and the mechanical advance from the distributor correct? Initial timing would be with engine warm and car at idle right? When engine gets rev'd to 2500-3000 range is that showing your total timing, with vacuum line plugged ? Does anybody know off hand what mopar sets the distributors mechanical advance to from factory? (new mopar distributor by the way with tan cap) My car does have power brakes and power steering, can I get away with not using the vacuum advance canister on the distributor? If not, what is the usual vacuum degree setting on the Mopar distributor from factory? Would my total advance be more in the 50 btdc once I added the degree amount from the vacuum to the initial and mechanical or with all three added together should it be around 36 degrees? Is it possible that when I hook up a vacuum gauge and get a reading that is in the constant 18-20 steady (normal) range off of manifold pressure, that this would be a good indication that the timing of the engine is pretty near where it should be or is this a bad idea? If bad idea, can somebody walk me through the best/proper way to get the car timed right? I do have an adjustable dial timing light and vacuum gauge of course. Sorry for the long posts and all the questions, but timing is not something I have done before so I don't want to just think it is right, I want to make sure I'm doing it right and getting the correct specs. Thanks again to all, Dave