Now c'mon, Tim. What we hoped to get from you was a list of the components to make a voltage regulator setup. Part numbers and where to buy 'em. And the official schematic showin' all the polarities. Eh?
For some reason, that reminds me of my days as a street rod parts salesman. People would come to me at shows and say "how much money does it take to build one of these here street rods?" My answer was usually "how much money do you
have?".
So, how fancy a regulator do you
want?
Igor's long wire works, and is easy to tune. Then if Frank likes the result, he can replace it with a resistor of the right size (resistance
and power). Problems that I can imagine cropping up with that approach are the resistor getting hot (but you won't be starting for long), and the starter having poor starting torque.
You can get almost infinitely fancy (hence my comment about how much do you want to spend -- it's a bottomless well).