coakgafamily,
I have a 3500RL with the rear jacks just like yours. My dealership was able to bolt on a receiver without disturbing the jacks. I do not have any pictures of this but will try to add a link to some CAD drawings I made an posted in another thread. They basically used a 2" receiver and welded on angle iron on each side. Then they bolted the angle iron onto (3) cross members of the trailer. I beleive the length of the receiver was 48 inches and that's how we were able to bolt onto (3) cross members. Anyway, it is very sturdy and secure. The welded construction actually fits between the frame and the jacks.
I hope this helps,
Mark
//heartlandowners.org/showthread.php?t=710