Charging circuit - reduced load on ammeter circuit

So far as "keeping the ammeter" while improving the circuit, there are several thoughts --not all my own-- which have popped up on the board occasionally

1...My own which I hope to experiment with this summer--involves adapting the circuit (on my 74 Scamp to the 76 year "external shunt" ammeter.

2....One of the guys on here talked about putting two diodes back-to-back out in the engine bay. These would not conduct or only partially turn on at lower charge rates and keep the ammeter operational while limiting higher values of current flow through the ammeter circuit. I'll have to see if I can find the thread

3...Another possibility might be using the same idea as yours, but with much smaller wire, and again--making sure the OEM circuit is operational and in good condition. This would act as a shunt that reduces current through the ammeter circuit while still allowing it to function. But it WILL NOT read smaller values, such as headlights and heater