I use a lever similar to PA24, except much smaller. My lever is made of 1/8" flat steel. I saw and file it until it is in an "L" shape with the long arm about 1" long and the short arm about 3/16" or a little less. Both arms are 1/8" thick. The important thing when making the tool is that the inside corner is square.
I pry the spring over until the short arm of the tool fits between the spring and the frame, with the long arm pointing outward. Put the stock of the gun up to the tool and mark the location and depth of the notch that is required to clear the tool.The notch will be cut in the thinnest portion of the wood under the lock plate. I usually cut it with a cut off disk in a Dremel tool, but other methods will work. The tool is held in place by the spring while the trigger plate is put in position and screws inserted and tightened. I then check the function of the safety before removing the tool, because getting the safety lever in the correct position is my biggest problem when re-assembling. Once everything is in place, push the top lever over to free the tool and remove it. If there is a need to disassemble again, the tool can be easily reinserted by pushing the top lever over and reinserting the tool before continuing dis-assembly.
