[351mustanger]

One size up on the pilot shouldn't keep it from starting. It may take a little cranking to get the float bowl filled with gas. Make sure you didn't miss a vacuum line. Pull the fuel line from the carb and make sure you get fuel flow (be careful of spilling gas, especially if you are close to a heater of some sort). If you get fuel from the line, put it back on and check that the float bowl is getting gas. I am not sure if you can get to the float bowl drain screw, but opening it will tell if there is gas in the bowl. Once again, be careful with gas and open flame. Also check the sparkplug to see if it is wet from too much fuel. Might as well check for spark while it is out.