Amp gauge shunt

Mattax thanks for your help. Your last diagram makes a lot of sense, the size of the shunt and the guage of wire should not be to hard to figure just by the amount of needle movement. What size shunt would you recommend would you recommend as a starting point using an factory amp guage that has been cleaned and re-soldered?

Have you thought about posting a thread in the how to section? The information I have found to say the least is not clear or just a "band-aid". As you know a large number of members have up-graded to late model Denso alternators and are following the schematics drawn by MAD Electronics and Allpar. The wiring just needs to replaced and the circuitry updated, not just spliced.