Am confused. The MSH doesn't do that.
Slide is off, right? Pull thumb safety. Grip safety will be loose, but stay in frame (if beavertail). Pull back on hammer a bit. Then while holding hammer, push sear pin out. Hammer can now go forward, and sear is loose in frame. Ignore for a sec. Then pull hammer pin. Pull hammer and strut out the top of frame. Now there is no pressure on mainspring. If MSH is still stuck, put mag well on your bench and tap out MSH with a brass drift.
That'll get the pressure off the MSH. If the issue is it's badly fit to the frame, some tapping will be needed. If you have a beavertail grip safety it will be locked in the frame by the MSH and the back of the frame. A flat screwdriver between the two and some careful twisting should push the MSH out enough to pull the beavertail and then you can knock the MSH out with a drift. A GI grip safety will (IIRC) be wiggled out with the MSH in place.
If you want to post a pic or two I can draw a picture.
Either way no need for an overpriced smith.