>> If that's the kind of bike mechanic you are then go for it.
Ah the Interwebs...
The OP says they have "no prior experience with these hubs".
The hub is functioning fine right now, as it will for another decade or two of daily use.
S/he was given GREAT advise when told NOT to take it apart.
This person believed the oil port was a zerk, and you’re telling them to open up the thing for no reason at all…
>> You will be amazed at just how filthy the insides are on an older hub
I'd say you'd be amazed at just how CLEAN the insides are on an older hub
Flush it, add some 20 or 30 weight motor oil and get out on the road.
I’d listen to your LOCAL mechanic who makes a living doing this stuff.