I had a truck stop do mine, because they had the cage it required, but I had mine done a long time ago.
You have to find some old timer like my father who has been doing it for years to get those rings seated just right during air up.
Generally I'll agree with the others, but with one big exception. If you have multi-part rims that look like this picture, you really need to start looking for replacements. These Budd style "side ring" rims use a Firestone outer rim known as an RH-5° design. These are the bad ones that reputable tire service shops won't touch anymore for insurance/liability reasons. "Lock ring" style outer rims made by Firestone or Goodyear are still serviced if they are not seriously damaged/rusted. Commercial big truck shops see these every day because demountable Dayton style rims in "lock ring" designs are still being sold today.
And that is for a reason, too. Rust can wedge the two rim sections apart, and it is a hell of a mess. Don't ask me how I know.