Hello all. My clock in the 220D isn't working. I have a replacement cluster that I want to practice on before tackling the real clock and cluster.

I see the clock terminals for power are brass and aluminum colored, with one brass colored male spade.terminal. Which is positive and which is negative?

I want to test this clock to see if it works so I am going to hook up 12v to the proper terminal to see if I get any readings.

__________________
71 220D 169K wrecked
83 240D 118K sweet 4 speed
91 350SDL (one of the 60% good engines) 156K
84 300d (loaner to my sister) 189K
79 300SD (partswagen)
86 420SEL partswagen
70 220d (partswagen)
68 280s GASSER!!! under construction now
85 300sd 310K miles winter beater car retired
93 300d 2.5 turbo 168K wife's car
83 280SL euro 5 speed 155K
69 250S newest project 54K