You should be able to use the factory key to manually open the door and start the truck. If that doesn't work, look into the manual. It should tell you.
1994 Ford Mustang GT
1990 Ford Bronco II
2001 Lincoln LS V8
1970 Ford Bronco
2006 Harley-Davidson Sportster Custom
If you don't already own a Ford (or Ford owned product), get one.