<VV> Upgrading from 3 speed to a 4 speed

[Robert Marlow]

keith osborne wrote:
> Doesn't the '64 differential have the special mounting provision for the transverse leaf spring?  So a '64 car can only use a '64 differential housing?
>   

Yes but no.  The, the '64 diff has the mounting pad for the transverse 
spring, but I have seen earlier diffs installed in '64s, and '64 springs 
installed in earlier cars, by simply letting the spring ride against the 
bottom of the diff case.  Not a good idea, but I have seen it more than 
once.

--Bob