have a 1987 ford f350 duelly 2 wheel drive pre-efi 460 and it wont run:surprise:. hasnt been registered since 2012, so it hasnt ran in a little over 7 years. we got it to start and run for a couple of seconds by putting gas in the carb. put about 5 gals of gas into the tank but it wont stay running. suggestians...