For a 1989 420 SEL, the standard alternator is the AL69X, 80 amps. I would like to replace it with something that has more output. I heard the AL129X will fit and cranks out 115 amps. Has anyone tried this swap?

Would I have to upgrade the wiring to the battery for the AL129X? If so, should I add a second strand of 10 Gauge copper, and use the existing strand too? Should I just use a one strand of 4 or 2 gauge straight to the battery? Does any other wiring need to be upgraded?

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1989 420 SEL