To much voltage

It would help if you told us what car you have. Unless you already have a later model with the funky triangular Vreg connectory, I would get an electronic regulator for the earlier models, since it would match your wiring harness, and is easier to connect if a custom harness. I bought one recently for $11 at rockauto. It is a thin shiny box with simple connectors that match the old mechanical Vreg. Make sure you ground one terminal of the alternator when using this Vreg, which is already done if you have the older round-back alternator.

In my 65 Dart, most all the wires thru the bulkhead now just turn on relays in an underhood box from a newer car. The 12 V IGN that I regulate is off a relay direct from the battery. wjajr is right that your problem is the drop thru the bulkhead and/or wiring harness, or ignition switch. Your Vreg is probably regulating the dV it sees correctly. We see that a lot. Also make sure the Vreg has a good ground to BATT-.