Anyone got an ex-Environment Agency Cube?

.. and figured out the additional (OE fit?) wiring into the box?

I've got 4 wires- all fed through the bulkhead cavity (which made me wonder if they're OE)

a) HEAVY duty perm live for the water heater- which is fused at the battery.

Light duty twin-core; live + earth for flashing roof beacon.

c) Medium duty earth(?)

d) Medium duty engine-switched live. Only live with the engine running, not with just the ignition turned to position 1 or 2- so presumably via a relay.. like a split charger(?)

Any help gratefuly received (as always!)

Cheers, CVM.