If you want your C64 to disguise itself as one of its cousins, the C16 or Plus 4, you're in luck - I've ported the C16 core from MiST:
https://www.patreon.com/posts/c16-plus-4-core-51768501
D64 images aren't yet supported, but it does support .prg files, .tap files, and even emulated a SID card.
Have fun!