my 79 Bronco (351M) broke down approaching a toll way and I can't get it to start unless I give it full throttle then it runs really rough on won't idle. I checked fuel pump, spark plugs, vaccum lines, drilled the catalytic converter, and it seems to be getting more rough as I try to diagnose the problem. Runs the same whether I poor gas into the carb or if it is from the fuel pump. Could it be weak ignition? All plugs are dry and there is no smoke ever. I know it is extremely lean, but I don't know why. Anything will help.