Two axle Jeep with short neck RGN- will it be practical?

I built a pin-on tag axle for my last truck. It worked fine but I still needed a long neck rgn to reach the fifth wheel because you can slide the fifth wheel back onto the pin-on axle

 

Would there not be a way to build a pusher axle forward of the drives, that is removable in the off season when you don’t need it ?

 

Nah, it would be more of a pain to take off and would weigh more than a conventional pusher.

 

You could remove the wheels and brakes in the off season, leaving just the axle and airbags. That would leave , what, about 1000 1200 lbs for the empty axle and bags ?