For a good number of the '61-'68 W100s & W200s the Warn "M7"
lock-out hub was used as original equipment. According to Warn
Industries, these worked on Dodge DANA 44 axles from '59-'74.
The "M7" is marked in the finger recess of the lock-out dial.

I recently came across some NOS Warn M15E lock-out hubs.
As with the M7, the "M15E" is also marked in the finger recess
of the lock-out dial. It is, in general, the same in appearance
as the M7. I am wondering if anyone out there has the M15E
lock-outs on their W100 ['61-'68] or W200 ['61-'71]??
Warn Industries also lists this as being used on '59-'74 Dodge
DANA 44 axles. Any information will be appreciated. I'm also
wondering if the M15E could be specific to the early 6 lug half ton
and later ['69-'74] five lug half ton DANA 44s?
John