Forgive me....PLEASE!

Picture of the rear end? Is it an 8-3/4? If it is, it probably has tapered axle tubes.
Sorry, I'm not by the car now, but yes, it is an 8 3/4" rear end & they are tapered axles with
keyways and castle nuts - and no adjusters - totally different assembly than 'normal' - unique to 1963 (maybe 1964) and older - maybe even back to 1957.