That is very strange. Not too sure what was trying to be accomplished there. Looks kind of like they were trying to lower the height of the deck (springs have been relocated to UNDER the rear axle) but then adding the other steel back on top negates that move.
BTW, mine is E40-4535 and here is its plate:
That reads: 6E40-195-7H1KD if you can't make it out. My rear axle was originally a single speed 7.2 ratio. It still has the 7,000 lb front axle and the heavy duty brakes but a 2 speed rear end of unknown ratios.