Have you done a search here? There are a gazillion posts on over-charging. Just search posts by 67Dart273.
I also vote on excessive voltage drops thru the wiring and connectors. Your voltage regulator is probably doing its job. All it knows is the voltage difference between its case to the blue wire, which it regulates to ~14 V. It is your job to see that the blue wire (at Vreg) is the same as BATT+ and that the Vreg case is the same as BATT-. If not, don't fault Vreg for over-charging.
