1989, Chevrolet, C1500, Silverado, 5.7 V8 engine truck. Single cabin. I recently replaced the alternator which was easy to buy at the local parts store. But for the life of me I cannot find the alternator one-wire pigtail. local auto parts don't have it and the ones I found so far has more than one wire. The plug is exactly as the one below but it only has 1 black wire coming out of it. The problem is, the one I currently have is so old and raggedy it's falling apart and won't stay plugged in. I need a replacement.

 

Looked on Rockauto - interesting that there are 2 and 3 wire connectors shown. Looks like the two wire one 2nd wire may just be a ground. Maybe ask dealer??

 

Welcome from Florida, If the 2 wire pigtails you find are exactly the same as your old except for having extra wires, you can use it and only connect the one wire you need and cut the extra ones off.