erm - when i was at college, my programming lecturer was a ms. helen grant, and the main thing she taught me was this: there is
always a way.
even if it means faking it.
take away all the ammo from the rearming truck. does this disable its rearm function when you get close enough? if it does, great. if not, then there'll be a defunct action in the player's menu.
name the truck, and have a looped script going in the background such that, when the player gets close enough, your own rearm action is added to the menu, which calls a script to instantaneously rearm the player according to whichever weapons are being carried/whatever weapons are in the vehicle.
it's a lot of work, and thinking about it, i'm unsure if it would be faster. there'd certainly be no waiting for the numbers to increase - the script would bestow full ammo instantly. it's finding out what weapons the player/player's vehicle has which would be the pain....
after ammo is restored to full, action is deleted. any questions? direct them to ms grant