Yet another Rear End ID

[kingburnett]

I need help identifying the rear end on my 1961 K10.
I know that it is not the original.
The cover on the rear has 12 bolts. The Axels have 6 lugs each. I took off the drum and and measured driver side shoes to be 2-inches wide.
The self adjuster is installed wrong.
Other markings on the drum were:Centruy max dia 11.060 Z12006 281 202.
Stamped on the end of the axel was KW 4360.
The number 3896839 with a 1 or I under the 6 is raised on the pumpkin housing on the front passenger side. There is a GM84 marking on the front driver side.
There is a date code looks to be 8Z1 ? Looks to be a GM Corporate 12-Bolt. I have no clue of the year. I need to fix the brakes, especially the parking brakes. Looks like the cables for the park brakes are all wrong for a K10. Probably came off of a C10.
Thanks for the help.