Where is your truck going to be? If you're going to leave the truck on the grounds as a towing vehicle, then it should have a pass as well, so you should be able to come-and-go in it.
They're usually pretty finicky about people coming and going without passes - whenever my wife would bring in her (non-mopar) car to bring in lunch, she'd have to pay the $50 admission to enter, and then get refunded it when she left. Such a pain for a 5-minute stop...
Best bet is to ask when you get there, unless your truck has a pass, in which case you should be fine.