well 2 hinges on one side will work fine to hold them up. more so in fact then the piano hinges you were talking about. piano hinges tend to be VERY flimsy. the problem lies more in what you connect it to the car with. cause sheet metal screws may gardually work their way out.
as for the truck boxes, isn't the reason they are so effective because they are right behind the driver. if you are looking for deep hard hitting bass, i'd say no, but if you're looking for a good sounding supplement, then it *should* work fine.
Chris
98 SVT
sony 660, kappa 57.1 all around, RF 800a4, RF power 500a2, 2 12" RF DVC's
