Fuel Delivery

The Fuel Cell is mounted in the trunk (55 Chevy) on a fabricated frame to allow room underneath, for the drop sump. I can mount filter and pump on the tank support frame, inside the trunk, then run the line through the floor and forward. Or, I can run the tank outlet line through the trunk floor, then to the filter and pump which would be mounted outside (below) the trunk, just in front of the rear bumper. This way, most fittings, and all the pressure line would be completely outside the trunk and driver compartment. This makes the most sense to me as all the line with pressure is completely outside the vehicle - all the way to the regulator mounted on the firewall.
I'm wondering if the regs allow the pump to be mounted outside the vehicle, or must it be in the trunk? There is a firewall where the rear seat used to be.

NHRA rules would require the pump and filter to be outside of the trunk.... I like to have a hole in the trunk floor the correct size for the sump to protrude through.... then mount the pump and filter to either the frame rail or crossmember.

Thanks Dave. That makes the most sense for me. I already have the cell mounted on 2 inch stock so that I didn't have to cut a huge hole in the floor. A -8AN 90 fitting will drop the line directly through the floor, then I'll mount filter and pump to the rearmost crossmember. The battery is also in the trunk inside a sealed box. The fuel pump will be powered through a relay from the switched side of my electrical cutoff plunger. I can see why the rules require the pump to be completely outside the vehicle. I just wanted to make sure it wasn't required to be inside some type of sealed compartment.

Might want to move that regulater off firewall,NHRA says FUEL distrabution blocks must be located 6 inches forword of the flywheel/bellhousing area.

If, as you say, you have a minimum 0.024" steel or 0.032" aluminum bulkhead attached to the rear seat area and also to the shelf panel where the speakers used to be, then you can put anything you want to in the trunk, including pump(s). The idea is that if you were to stand the car up on its grille against the wall and fill the trunk with liquid, no liquids would enter the driver's compartment. Make absolutely certain that the bulkhead is liquid-proof. Have a buddy inside the car at night to observe while you shine a strong flashlight all around the trunk area. He should see no light.