My 85 4wd d50 needed a tank skid plate. Lots of banging going on with that long overhang "long bed". I always wanted to flatbed that truck and relocate a custom tank ahead of the rear axle, maybe up to the bottom of the flatbed which would be at top of frame arch at the rear axle. The pickup has a really good approach angle stock, and with a bobbed rear end, to no more than a foot behind the rear wheel, it ought to slop around really well.

Not responsible for advice not taken...