The 1947 - Present Chevrolet & GMC Truck Message Board Network - Almost ran out of gas, now I'm having engine trouble.

Hello guys,
It's been awhile, but I need help again and y'all are the experts.

I did what I shouldn't have done and let my truck get low on fuel. I was in a hurry to get home from work and didn't stop by the pump thinking I had enough to get some in the morning. The next morning it was cold and I let the truck warm up I got in and remembered I needed gas immediately. I almost got to the gas station and it backfired as I rolled up to the pump. I filled her up and she backfired through out the intake the whole 5 miles to work and when I parked it idled like crap. The night guy picked me up a new fuel filter and I put that in and it fired right up and idled smooth. On the way home the first time I gave the pedal a good push it bogged down and back fired through the carb again. I limped her home. I checked the fuel filter again and it was clean. I had fuel at the carb but everytime I hot the throttle it's backfire through the intake. I then replaced the fuel pump. It started up but wouldn't idle and was spitting gas out the carb. I assumed I had worked junk all up into the carb. I replaced the carburator and it still wouldn't idle, it's not spitting fuel everywhere now but it's flooding. I pulled the plug and they are dirty, fluffy black but not wet. I'm going to replace the plugs, and see what happens but I am sure I am missing something. Could the initial backfiring have thrown off my timing, or broke the timing chain? Did running some crud through the carb get down to my spark plugs? Anything else I should be checking?
Thanks in advance, I know I'll get some great replies. I'm not a mechanic, I just know enough to get myself into trouble, but it's fun.

Mike