Good catch Mike, that lift bar makes me think it’s a USAT diesel, also with the square pin at the top of the coupler.
I agree, looks like someone put it together wrong. Stanchions on the right are bent.
Look at the video of the GP30 on their site, seems to be the one.
Also, it’s hard to tell, but maybe someone broke the right hand “finger” off the center step plate? it looks shorter than the left hand one but I could just be the picture.
You can get the instruction manual on the USAT site, besides watching the video where they assemble the railing.
Greg