There is nothing wrong with ammeter. The reason people bypass the ammeter is the connectors in the bulkhead connecter. The terminals are relitively underrated for the loads they carry. That and 50 years of thermal cycle and corosion.
If you run only the stock accessories etc. and clean and tighten the terminals in the bulkhead connector you should be fine for another 50 years.
Now if you have added high amp drawing devices, radio amp, electronic ignition, etc you could be in for a meltdown.
There are a few things you can do like use a relay for your headlights, use LEDs for the other lights (be sure to get a LED compatible blinker and emergency flasher)