Rear wiper wiring routing?

Hello
I have a wiring issue I'm hoping someone can help me with please.

200tdi defender 90 (possibly 1990 or 1991 but on a Q plate so not sure). Round type rear wiper wash switch has four wires to it:

double green 0v when ignition off and 12v with ignition on so seems OK

Double black earth seems OK

Brown/light green has 0.7v with ignition off and 1.5v with ignition on. At the motor end this shows the same but rises to 5v when ignition on and wiper switch activated.

Red/light green as per above but rises to 12v rather than 5v

New motor seems to run OK but "parks" extremely slowly (is that because of the 5v?)

Anyway what I need is someone to help me with the exact routing of these wires from switch to motor as I'm guessing there's some contact being made between wires that shouldn't be touching. Failing that the name of an auto electrician in the medway / Kent area please.

It comes from the cover in the OS rear then through a flexi plastic tube into the door,in said tube is often a fail point on older land rovers

Thanks tottot I'll have a poke about. Do you know how it gets from the centre of the dash to the rear of the vehicle?

Through the big grommet on the engine side bulkhead down to the os chassis rail through the chassis full length pops out behind os rear wheel, into tub under the rear light inner cover.

Thanks flossie