I had a 1966 c20 and i have a special socket that fits in the opening to remove the large nut.Follow what 1958gmcnut said,it's not hard at all.You can use rtv silicon to make a gasket for the axel shafts,or buy them.If i remember right,my 1966 had metal axel gaskets.

If you need a picture of the socket,i can post one.

1951 3100 Chevrolet
1951 Chevrolet Suburban Carryall
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