There will be modification required, but I'm guessing the two rears will be very close to the same width.
It is possible to get the pumpkin from a 55-59 chevy with an open driveline and swap it in your rear housing. It would still be necessary to modify the axle mounts for this to work. You could order a 3.38 gear set for this rearend. However you would have to swap transmissions in order to do this swap.
