That's the way I do it. You backprobe the voltage on the pot pin - 6 on LH2.2. Then you have a reference for this adjustment and the next. The range is 0-2.7V and the 380 ohm point is at 1.5V - a good mid point, as the pot is linear but the resulting voltage is not. Working with voltage, you know right away when you reach the stops (or non-stops) at the end of the pot.

I've never had a regulator's vacuum diaphragm fail as it most commonly does, but I've had one run well above pressure when its spring fell out of place. That kind of rich can also be caused by a heavily contaminated lambda that has a hard time recognizing rich until its been rich a while (lazy O2 sensor).

The backprobing works with the temp sensor too, though you need to do it on the ECU plug for convenience - pin 2. With the car fully warmed up the voltage should be 0.5 or less, 0.5 being the equivalent of the 176 degree point on the resistance chart. 68 degrees makes it read about 2.25V and 32 Fahrenheit works out to be 3.25. If you see it 4.5V or higher you better have your long johns on and a place to warm your hands.

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Art Benstein near Baltimore