Wolf 90 FFR wiring confusion

[Mark8063]

Hi All

i am new to the group and have a bit of a problem with the wiring on my Wolf 90 FFR project.

it would have had two alternators but the auxiliary one has already been removed. All the radio junction boxes etc, radio batteries etc have also been removed. I am left with the vehicle batteries and a partially disconnected FFR wiring. I understand that on the bulkhead behind the seats there would have been a twin alternator ecu and a big fuse called a fast fuse. 
 

I therefore have an auxiliary wiring loom that terminates at the missing ecu and fuse. This loom runs through the seat box and up into the engine bay where I guess it splits and connects to the vehicle alternator and would connect to the missing auxiliary alternator. the vehicle alternator is fine and the vehicle starts and runs well.  I am not desperate to remove all the FFR wiring as long as what remains is safe.

The old auxiliary alternator had a thin brown/yellow wire attached to a small screw terminal. Even though the aux alt is gone the wire is still live and I am wondering where this live wire goes. With the auxiliary alt gone I would have thought any wires that were attached would be dead.

I am not great with vehicle electrics as you can probably tell.

Has anybody else done this before and can offer any advice?

Thanks

Mark