[Hank70SS]

I wouldn't say a 1 wire is no good but there are better options. The old Chevy's used a 10DN or 12 DN external regulator alt. The voltage sensing was done at the main junction of the electrical harness near the horn relay. The voltage at the alt can be higher than at the main junction due to voltage drop across the alt output wire. A 1 wire senses voltage right at the alt.

You can use a 12SI alt which is similar in case design to the DN alts but has an internal voltage regulator and higher amp output. The mods to the wiring are pretty simple and it will maintain voltage sensing at the main junction. Or you can stick with the original type alt and external regulator, upgrade voltage regulator to a newer electronic voltage regulator, no wiring changes required. I still run the old style alt. and voltage reg but I don't have any high demand extras like audio amps, etc. so it works for me.

If you want to upgrade your alt to a newer internal regulator type, let me know. I'll show you where to get a wiring diagram of the changes you need to make.

I guess I should ask what alt do you have now? Do the 2 terminals where the wires plug in look like this || or like this --. Post a pic if you can and tell you what you have now.