I want to start driving my project but don't have it painted yet.  Wanted to know if anyone out there knows if it will be safe to drive it in primer.  There is no bare metal but I don't want rust forming under primer on metal that has already been fixed if it gets wet.  I plan on painting next summer.  thanks  

By "There is no bare metal" I'm guessing that you mean you have primer over an old glossy top coat? The key to whether it is "safe" or not is if your body parts are sealed from moisture. There's a lot of questions you need to answer. Does the truck sit outside or in a garage at night. in AZ, or a rainy state? If you have any doubts just throw a quick enamel job on it.