You don't need any fancy diode module, just two 5 amp diodes from Maplins at about 98p each.

Fit stop and tail light holders to the inner lamps

(from scrappy, most Toyota ones will fit if they have wires coming off and don't connect to a pcb in the cluster).

Wire the inner tail lights to the outers.

Wire the two inner brake lights to each other then take one of the diodes

(I included a switch here so I could turn off the inner brakelights if Mr MOT got fussy) and connect from the outer brakelights thru the diode and switch to the inner pair.

Next connect from the fog light feed to the inner brakelights thru the other diode.

The diodes stop the outer brakelights from being on all the time when you put the fogs on and stop the tell tale dash light for the fogs from lighting up when you press the brakes.

The band on the diodes needs to be to the bulbholder end i.e.

the 12v comes out there.
