Bill,

Before U go spending money on a new GP cable, test the old one.

Here is the straight poop about the cable connector numbers and cylinder numbers, at least for a '79 300SD:

Cylinder Hole #
__________________


1...........2

2...........1

3...........3

4...........5

5...........7

So do a continuity test from each GP terminal to the metal in the GP connector using the chart above. If U get a low resistance reading for each of 5 tests, the GP cable is OK.

P E H