Ok, I've had a look through the haynes manual and it seems to be a simple relay connected with an PNP transistor to the v+ of the alternator. I'm quite competent with electronics so that's simple enought to build, however the guys over here seem to think that the relay upps the REVS to keep extra current flowing AND it has a timer to switch off the heated after 5 minutes,....

Haynes doesnt seem to show this, so whether it simply isn't true OR both circuits are built into the relay I don't know.... If it's the lattter then i'm going to have to get the FORDS relay, an expenive part i'd assume :/

Anyone know?