I think I would buy the 21.99 Maplin kit instead
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and an extra solenoid for the rear door.
I've fitted mine to two front doors so far and just working out best way to fit rear door one. Thw two front doors were really easy to fit.
Mine is a base 05 Defender with the alarm and cdl. I had the alarm configured at local independent which was easy. They just needed to set-up the two remotes and activate. Works great. I think all TD5's left the factory with the larm fitted. You just have to activate it.
Rather than hook the maplin actautor I plan to hook the solenoids up to the output of the alarm ecu for the factory fit solenoids. So that CDL will work off LR remote and key in drivers door lock.
The rear door uses a weird way of actuating as the rod is in the top of the lock. It uses an 'L' piece that rotates and connects the rod of lock and rod of solenoid together. This enables the solenoid to be installed under the rear wiper motor.
regards
Steve