Sounds like a fuel starvation problem. A vacuum leak would make the engine run rough, even at idle. Since you have a new fuel pump and fuel filter you've eliminated the usual culprits. It could be the line from the tank to the pump is clogged with something but I'm not sure how to check this other than disconnecting the line at the inlet to the fuel pump and see if fuel is running out freely. The only other thing I can think of is maybe a carb float problem. Hopefully someone else can come up with some other possible causes. Good luck!!