My 87 190D 2.5 N/A is gonna get a new feedback potentiometer and I was hoping someone has done this R+R before? How is the best way to get the voltage reading? Gonna do the 3 vacuum elements as well...Any pointers? I also noticed that the 1987 supplement states that the voltage is a much tighter number than the previous models; 2.4 to 2.7V as opposed to 3.9 to 4.4V........anyone know why? Thanks! Clip