Our '14 HC, 38'/12,000#(in spite of their on line specs)arrived with - gasp - 5200 pound suspension. After a bunch of research found that the only difference between a 5200 and 6000 pound suspension was one more spring leaf and a slightly larger outer bearing. It now has 6000# suspension. Leap ahead to the 7K suspension, you have exactly the same 3" axle tube but have a larger bearings/hub and one more spring leaf and 8 lug wheels. The OEM tires - same load rating though some if not all of the Montanas have Sailuns or similar heavier tires while the HC
may have a junk China Bomb. Mechanically, the frame bracketing is the same though the Montana may have the next step up equalizer.
Your possible 294RL fully loaded has a GVW of about 15,000 pounds, the 2300 pond oin weight when loaded will probably be closer to 2500. 15000 - 2500 = 12,500 on the tires. Divided equally is 3125 per tire/wheel. Kinda tells me that you need a 7K axle under a 294RL if you load it fully.
That 294RL is a nice floor plan though