Ok, I think I understand what you want. You want aux hydraulics (rear remotes) that will work along with the FEL and 3pt. Right? The backhoe should have nothing to do with your desires since it is PTO driven and not tractor hydraulic driven.
The 3pt should work when the FEL is connected once the backhoe is removed and any/all 3pt restraining devices or other manual locks have been removed.
On later model Kubotas (and probably your 7100) the loader is connected to a hydraulic block which is simply a tap into the hydraulic circuit. Some models have an additional hydraulic block which is used to connect a rear remote valve. On models without a second hydraulic block, the rear remote valve is connected between the loader valve and the loader hydraulic block.
If you can't post the hydraulic schematic, just follow the 3 loader hoses that don't go to the lift/curl cylinders. One should go directly into the transmission tank/sump and the other 2 should connect into a hydraulic outlet block.