Mark.....you need a 55 up 10 bolt truck dropout
Pull all the old torque tube and drop-out
Change thw two top studs to the longer ones from the 55up.....and the two lower
Put the 55 center in your original housing put the original side gears in and install your axels
Put on the tires
Put the truck on the ground
Pick your driveshaft angle
Stitch-weld the pillow blocks so the whole darn thing doesn't fall and 'PO GO' you
That's it!