I've had occasion only once to r&r rings, on a K&B .35, Frank, but had success by pressing the ring into the groove opposite the gap, which causes the ring ends to protrude slightly.
I then used the tip of a scribe to gently (spread if necessary) pry and lift the end of the ring just enough to let it rest on the piston above the groove.
At this point, gently lift the ring out of the groove a bit at a time, working your way around the piston.
Once it's out of the groove it should slide off the piston easily.
A lower ring can be treated similarly, except it may be better to work it down the piston skirt rather than try to work it over an upper groove.
With the ring setting on top of the piston, downward thumb pressure on it at one side of the gap will start the ring over the edge of the piston. With the other thumb gently work your way around, 'til it's possible to slide it down into the groove.
If you plan to reuse the rings, and if they're identical (I don't know - maybe some aren't), note which came from where as the upper may be more worn, so that installing the lower in it's place may give better compression.
Also note that some pistons have locating pins in the grooves to prevent ring rotation - doesn't affect removal so much but it's best to start replacement with the gap directly over the pin location so spinning the ring into position (with possible scoring) isn't necessary.
Best of luck with it.
Terry