I need to get the rear of my 1993 Mustang sealed up. I have a roll cage in it and the rear bars terminate right next to the rear shock towers. I have a Summit foam filled 10 gallon fuel cell sitting where the spare tire used to be. Nothing protrudes down through the floor. It is all inside the trunk area. I also have the cheesy cardboard rug piece out off the rear deck where the rear car audio speakers used to go. So there are all kinds of holes in the metal that the carboard carpet piece used to sit on so you can still see down into the trunk through the rear window. I guess my question is what will suffice to get this thing legal to run with both the fuel cell and battery in the back of the car? (I do know about the cut off switch for the battery and I already have that mounted to the rear bumper and wired to the battery) Sealing this thing up air tight where nothing will ever come in from back there seems a bit impossible. I've also seen the rear seat delete kits but I don't want to go that route. It would just have to be modified anyway so it would fit in around th roll cage bars. Does anybody have any advice for this? Or do I just buy a sheet of aluminium or metal, cut to fit and put it in? If anybody has any pictures to post that would be most helpful as well. I'm still just trying to figure all of this stuff out on my own. Or I should say figure this stuff out with everybody here helping me out. This place is my only resource for such info. Thanks in advance for any input you have.