Thanks for the info! The draft you have is well put together and I think adds clarification to a confusing subject. That is a good point on the fifth wheel hitch restriction, I forgot about that. I am assuming to get the restrictions removed you would have to redo the whole test with the correct truck (air brakes and fifth wheel).
You also mention a good point about the trailer used, as I would have done the same thing with a gooseneck trailer just like that.
My goal is to build somewhat of a multi-purpose vehicle, with flatbed (maybe dumping) and a gooseneck and ball hitch, which would basically preclude being able to use a full fifth wheel set up. I might need to rethink how I approach the project. Having a fifth wheel would allow a trailer like you mentioned with the axles set back.
Unfortunately the trucks I am finding are a few hours away so going to look at them to assess condition/determine info on the tags gets to be a challenge!
Here are three I have found so far. Truck 1 I think is a C60H, 24k GVW, cast spokes and full air brakes and factory tach, $1,800. Truck 2 is already set up almost exactly like I would do it and in good shape, $5,000. Truck 3 is cheap but unknown mechanical condition at this point other than I know it has hydraulic brakes, $750. I keep leaning towards truck 1 but I think it is in the worst shape body wise and has no bed or hydraulics.
