I just bought a new wiper switch "for Scout II" (the round kind, with "internal breaker", blades labelled B, W, 1, 2, 3), to replace the worn-out original switch (square, with breaker box on the side, with blades A, F, W, etc. as shown for all models in the service manual), on my '79 Terra. Using my trusty multimeter, I could not match up its contact states with the contact chart for the original switch. My Terra has the original motor and dash wiring harness. Does the new switch require a different type of motor/harness, or has anyone done some mods. to get it to work with the original? Thanks...