I've got a mid 80's mustang 440 with the Ford gas engine. We had it overhauled by a mechanic in January where it would start up no problem. Only recommendation from the mechanic was to keep on top of the fuel filter as it the gas tank was flushed out quite a few times but could still have sediment (dead mouse was found). Used it until April then it sat. Now we can't get it running. We've got a new fuel filter, all the fluids are at the right level. It'll crank forever, kick once with starter fluid then go back to cranking. A few times it kicked and ran for 5-10 seconds then went back to cranking. I'm not mechanically inclined but this damn thing has to be so close to working. Just don't know what's wrong. Spark plugs look brand new still. Fuel is flowing from the gas tank to the filter, not sure how to check if it's going to the engine from the filter. Filter is half full and doesn't look like it's flowing but maybe that's normal? Any help is appreciated.