Heated rear window wiring question

[evilC]

Mines wired up as Rich's but one mod I was pondering was to use a timer relay so that I don't leave it on for long periods. I will no doubt use it this autumn/winter and then I will get a better idea of the demisting speed to see if a timer relay can be set for the job. It ought to be a simple substitution of the original relay under the rear seat.

Clive