I can not answer that as I have never taken a gerstenberger apart. If you remove grips and hammer and take close-up pictures of the frame and hammer maybe I could make suggestions. But it would be really just general suggestions without actually having the gun "in-hand". Likely shortening the spring and maybe removing the the little hooks that are on one end of the Smith spring. But again without seeing your gun (apart) these are only possibilities, a Smith spring may not come close to working.
Just walking on the edge of of my grave.