Just start with 1::a: for the first 96 bits and duplicate the entire ipv4 range into the remaining sections (I.e. 8.8.8.8 would become 1::a:8:8:8:8) which would still leave a huge amount of space open from a's-f's being technically available as identifiers (i.e. 1::a:8:8:8:f would be a valid ipv6 address).
Then, as people stop using NAT, let them have access to the 1::b: section, and if that section ever gets filled, 1::c:, etc. Once NAT is sorted, roll out routers that would NAT ipv4 to 1::b: addresses so that they are in both locations at the same time.
It's easy enough to mentally switch to using colons instead of periods, and everyone could also easily memorize their opening "street sign" or whatever it is called.
Just start with 1::a: for the first 96 bits and duplicate the entire ipv4 range into the remaining sections (I.e. 8.8.8.8 would become 1::a:8:8:8:8) which would still leave a huge amount of space open from a's-f's being technically available as identifiers (i.e. 1::a:8:8:8:f would be a valid ipv6 address).
Then, as people stop using NAT, let them have access to the 1::b: section, and if that section ever gets filled, 1::c:, etc. Once NAT is sorted, roll out routers that would NAT ipv4 to 1::b: addresses so that they are in both locations at the same time.
It's easy enough to mentally switch to using colons instead of periods, and everyone could also easily memorize their opening "street sign" or whatever it is called.