If there ever was a trick to the steering wheel, it would be everything you can think of. They are notorious for sticking on permanently. gmwillys has success with a few methods. He will help here. I tried everything I could think of. The end result was a Do-More with a cut off blade. I had to remove the wheel completely by busting off what was left after all kinds of tries. I had to cut the hub open and use a chisel to split it open off the shaft.

The rain just sits on those splines when they are exposed. It will rust into a single piece. I would start by soaking it with your favorite rust penetrate. Rust Buster, Kroil, even WD40. Soak it for days. Use a heat gun on the hub, but not too much or you will melt the wheel. By far don't even start without a very good puller that contacts the hub and not the wheel. The wheel will bust immediately if you pull directly on the cover. https://www.kaiserwillys.com/product...6-jeep-willys/

There are a few good sources for the steel. A few people on the site are working on the body. I am sure you will get some good sources. I used KW on my tub kit and I was satisfied. No steel you buy is going to fit just right. You should expect to have to do a little "correcting modifications".