Ammeter Bypass a Must?

To your question. Is it a must? No. If all your wiring is in good shape and ALL you need is a good ammeter, I would just replace THAT. On my 64, I inspected everything very closely when I got it because I was aware of that issue. But everything on this car looked great, so I cleaned everything up on the back of the cluster and it's been working fine since I brought it home in January of 2019......after it had sat in one spot since about 1980 or so. It's still working fine.