most jeepers should move their vac-can up into the engine compartment, they usually are alot safer up there, especially once you start cutting out chunks of fenders and inner fender-wells for bigger tires, or if you just like to bump into stuff with your bumper, if i remember correctly, doesnt that little bottle keep you in 4wd??
plus if your like me, you can use those same spots behind the bumper as a perfect "hidden" (depending on how cut up your front is) mounting spot for a couple of PA horns 