54 Winch fill plug fitting size?? P/N?

It's a little hard to make out the parts diagram but it looks like that's more than just a fill plug. Seems there is also a filter vent involved.

How about a screen to filter out accidental large chunks? The vent might work to keep reduce condensation. The oil that drained was a milky mess.
If I can't locate a P/N, I will then cut the fitting in 1/2 and get a 1-1/2, 1-3/4 pipe fitting welded on it.
As for a vent, I might drill small holes (4- 1/32" at an upward 45 degree angle) in the cap and call it a vent.
I did get the cable retainer plate figured out. I wound up shaving it down to fit inside the cavity to retain the cable ferule. I also had to recess the head of the bolt a tad bit to get it out of the way of the cable on the drum. It's about done once I get the fill cap fitting dialed in.

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Here's the parts info on the fill/filter/vent area for that winch.

Thank you for the illustration, I will give CAT a call on Monday and get the bad news.

The 6K6977 Cap, $42.48 and the two gaskets are available but not sure on the Adapter 8P2330 [plug], have to call on that.