That looks like an RV type trailer frame. Zieman? Do you know the GVW? If you say those axles are 2700# (unless I misread) the GVW may be only like 5500-5800#. If it is, then you will most likely be over weight with two rigs on it. I hope I'm wrong. The GVW might be stamped in the frame somewhere near or on the tongue possibly or even have a data plate riveted to it somewhere.
I just would h8 to see you do something like this and then get all bummed because you find out it wasn't safe, that's all. Otherwise a good project! If at the very least it will fit one truck and lotsa other stuff.
