White must be coil+ (86) and black coil- (85). Look at the numbers on your relay. The coil draws very little current (~30 mA), so shouldn't matter where you tap +12V, but you want either IGN or ACC which isn't powered when the car is off. BATT+ would run down the battery. I don't think A's have ACC under-hood (horn relay is always hot), so IGN is your only choice. Tap that on the upstream side of the ballast resistor (if you have one). Simple since 57 teminals and you can buy piggy-back terminals. I don't understand their temp sensor. It must be an on-off switch which turns on when hot and you must power one side w/ 12 V.
