My passenger car service manual lists 30 amps as the standard current regulator setting in 61. I don't have the truck manual handy right now. Either one should work OK, however. The only time the generator is going to put out maximum charge current is right after starting, for a short time until the battery recovers from the starting load. After that, it will drop back to 10 amps or less.
Is the battery going down? I can probably check and adjust the one you've got, if you're interested. We're only about 20 miles apart, it seems. Email me at [email protected].
Jerry

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