dabac

A worthy intention.

Yes.

Not a nightmare, a tad more difficult than servicing a wheel bearing. Somewhat fiddly, and bodies aren't that pricey, but very doable.

Here's a photoguide on how to do it. The language is Swedish, but there are plenty of pics.

Key points translated:
it's recommended to replace the ball bearings, you need 50 balls in size 1/8".

Removing the dustcap w/o warping it too badly is often the hardest step. Gentle prying with wide screwdriver is the suggested method.

Loosen the Allen bolt holding the body to the hub just a little before you hit the bearing cup. Once the cup has broken loose you can then remove the Allen bolt all the way.

You need a "special" tool measuring 29 mm wide and 2 mm thick to loosen the bearing cup that holds it all together.
I used a file that I thinned out a little at the corners with a bench grinder, the guy who wrote the guide used a cone wrench with the prongs cut off. Aluminum won't cut it, but otherwise it's not that picky. Removal is clockwise!

Sticky grease is recommended to hold the ball bearings in place during reassembly, while something more fluid is recommended for the pawls.

Let me know if you need anything more translated.