[ChevLoRay]

We don't want the tank in the cab because they can make the cab smell like gasoline. That would be because the fuel lines are old, and/or the fuel fill hose is old/leaking. When the trucks were new, they didn't smell like gas.

As for relocating them to the rear of the chassis, it frees up space behind the seat, and/or allows for different seating.

Simply relocating the tank to the rear of the chassis doesn't negate the possibility of damaging the tank in a rear-end collision. Fuel Cells, as I understand them from a racing concept, are supposed to retain the fuel, even if damaged. A tank, if damaged, will leak. Whether it leaks, or not, will be determined by the construction of the tank, versus the force of the impact.

In my first vehicle, I carried a one-gallon gas can. It was placed in the back left corner of the trunk, directly beneath the tail light. I had a '54 Ford 2-dr. I got rear-ended by a then-new '65 Impala. Ford was nose-down, in braking to keep from hitting a car that had stopped just over the rise of a hill. When I hit my brakes, the Impala driver hit his. His front end was nose-down. When he got hit by a fourth vehicle, it drove the front of the Impala into the rear of my Ford, and knocked me into a '64 Chevelle. The rear of my Ford was crushed to conform to the front of the Impala.

That can of gas?? It, too, was crushed to conform to the damage in the trunk of the Ford. It didn't leak. I have never kept a can of gas in a vehicle, since then.

Having once owned a '71 Pinto, which Ford recalled to install a thick plastic shield between the rear axle and the gas tank, I have to consider the location of the gas tank as very important. I think I'm just gonna replace the rubber and leave my tank in the cab.