Hitch Receiver info needed

[jeririgged223]

I have a 2018 Keystone Montana 3120RL Legacy that currently has the 300 lb receiver on the back rated for a bike or cargo rack.

Here's my question.... I want to take our HD Ultra Roadking with us now and then so I want to put a dual wheel swivel trailer on the rear. It comes with dual receivers so I need to reconfig the trailer hitch area with dual receivers.
I've seen it done so I know it can be done, just wondering exactly how it was done or should be done.

Without all the discussion about tongue weight, warranty, blah, blah, blah.......... the trailer and MC weigh about 1400 lbs together and we have no idea what the tongue weight would be due to the dual receiver distribution and the load being center of the trailer / forward of the rear wheels / axle.

The current bike / cargo config is has a metal tube welded to a smaller metal tube that is then welded to the frame rails. Not spot welded, welded all the way around on both sides. If we add two receivers to the existing rail, weld straps to the top and bottom of them to beef up their support, beef up the front and sides contact points with gussets could this possibly be sufficient.

Any suggestions to make this a class 2 or better would be greatly appreciated.