It was 19mm-easier to get to from under the car.
Installation was pretty straightforward, other than having to swap the pulley over from the old unit to the new one (which uses an internal fan, rather than the external separate deal on the old unit)-needed air tools for that.
I soldered high grade ring terminals on the end of the old harness wires-looks great, now we'll see if it holds up (Thanks Steve).
"If everything seems under control, you're simply not going fast enough" --Mario Andretti
1995 E500 street car
1986 Porsche 944 Turbo S track car