I can only speak from my own experience. When I removed my stock 1960 suspension I thought it would easier to remove the bars before I pulled the suspension. This turned out to be impossible, so the crossmember came out with the torsion bars still attached. Just for the heck of it, and to make the parts easier to dispose of, I thought I’d try to remove the bars from the lower control arms, after the suspension was out of the truck. Eventually I was giving a full swing with a 10 pound sledge hammer, and they never budged at all. After 40 years they were permanently attached.
If yours have been there for a while (probably since new), likely they are safely going to remain right where they are from now on.