Rear axle, seal surface thread pattern

[dirkbalter]

Hello,
As I am rebuilding / re-assembling my rear axle, I came across the seal surface threading (see pic) in the BBB. My seal surface looks good but does not show any signs of a thread pattern.
I am concerned that “sanding” a thread pattern would lead to a premature wear of the seal lip?
Any opinions?
Thank you

[Shvegel]

 The illustration is likely from an earlier model using leather seals. The feeling was if any oil escaped the thread pattern would sort of push it back into the housing.  Not needed  And counter productive woth a modern rubber seal.

[dirkbalter]

Yup, I agree.
Thank you.
(BTW, its BBB passenger cars 1959, mod October 63)