66 Mustang Wont Start

Hi all... Totally new here and I'm totally stumped.

I have a 66 mustang with a 289. It was running great and then about a week ago I went to drive it and it started missing really hard under load when I would step on the gas.

The next day it wouldn't start at all. I check the fuel - no water.. It's fine. I then checked my timing... Nothing had changed...still good. I checked my dwell... Still good. Checked for spark at the plugs and its there but I put a new coil on anyway(I replaced the entire egnition system about two months ago- wires, plugs, cap, rotor, condenser, etc). Then I thought maybe it was the carb(2 bar). So I yanked it and rebuilt it. Still nothing. After all that I decided to pull the cover and look at the timing chain... It appeared to have jumped a tooth because the dots were off by one tooth(and everything seemed stock so I am assumed no one had degreed the cam). So I replaced the chain and sprockets.

Still won't fire.... It sounds like it wants to but won't. I am out of ideas and very frustrated. Hoping I am missing something simple. Any help would be really appreciated. Thanks.

Checked battery, it's good. Changed the plugs with same style(per autozone and the book). Fuel filter is good and lots of fuel to the carb.

I did actually get it running today... But really rough. It idles horribly. When I first got it started it ran better than it ever has for about 30 seconds... Then without me moving my foot on the gas pedal at all it sputtered out again. I can get it to run now... But really badly. I can see the fuel in the carb(both from the accelerator pump and in the barrels when I give it a lot of gas). It's definitely getting fuel but still runs horrible. I started messing with the timing but still not making a difference.

Where should I be looking for this ground wire? Could that be the issue causing the plugs to fire inconsistently? Thanks again for the advise.

Ok... New update....

It was a point distributor, but I decided to pick up the Pentronx electric ignition upgrade with the new coil that goes with it... The one that fits into the existing distributor housing.... Put it in and she fired right up! Let it warm up for about 20 minutes.... Checked the timing to make sure it was good... And went for a drive. She was running amazing and then she suddenly died... Not like sputtered out... Like died all at once like I lost all spark. I checked everything... All connections are solid. Any ideas?