Would a Jumping Jack work for what you want? I have a friend with one, he likes it quite a lot for hunting and taking his quad. He's towed it all around the West.
http://www.jumpingjacktrailers.com/features.html
A M101A2 or M105 military trailer with extended frame to the front and two Moto rails with tie downs.
They are cheap, stout and would work well behind the MOG.
Here's my custom Kamparoo with 2 dirt bikes:
Any issues with just one bike on the back and instability? I thinking of trying that with mine. How much does the back bike weigh?
Hansrober: looks like you need weight distributing hitch and firestone airsprings in the back of the Jeep
I am looking at the possibility of buying and adapting or just building a trailer for camping. However I always like to bring my motorcycles along as well and I haven't seen too many designs that have this.
For years we have been developing a unique suspension and finally got everything right. SNIP