How are you supposed to remove the speedometer cable

Oh **** forgot to comment on this I found I didn’t even see that the small bolt above it held the cable in cause I couldn’t take that big nut off, but that smaller one came off and everything came out easily
That's because the big 'nut' is crimped to the cable. It does not turn seperately from the cable housing.
This is correct on an original cable at least through 1967 models.