I have some rims
with warpage at the lug holes. Any homemade options for improving/fixing?

Thanks

oversize lug nuts are available. Google is your friend

When in doubt, throw them rascals out
Ford lug nuts are bigger O.D.on the socket size, maybe they have more contact to the tapered seats on the wheels also
Stay safe

Check with Resto Rick, I had him repair a lug nut hole on and H wheel for me once. I also have a 68 JK wheel I may send him.
Matt

Maybe an arbor press & some flat steel plates. A metal plug type like in the shape of those round magnets found on stereo speakers.

Tried this today with a breaker bar. Got pretty good results, but a ton of work. Haven’t tried heat yet but that’s next.

Nice alternative to a press. Maybe just "massage" them down with a hammer/dolly

Those rims need to be repaired properly or trashed IMO. The metal around the holes is displaced and fatigued and will return to that state once a lug nut is torqued to spec. I would not use them for anything more than a roller to move a car.

after you fix the holes, use the newer style "bulge" nuts. available in chrome or zinc [?] plated steel. another tip to prevent your problem from reoccurring, is to find a washer with a 1/2" through hole that is slightly thinner than the seating ridges, grind the sides to fit the recess area, then tack weld into place. the washer will prevent the "pull through", and the "bulge" nuts will spread the load over a larger area of the wheel taper.
just be sure the washers and weld tacks are BELOW the mounting surfaces of the wheel[s]. i have done this on a few wheels with great success.