Sjones, make sure the pistol is not loaded. Put the hammer at the half cock position, and the safety roughly halfway between on and off. Wiggle the left side out. Once it is out you will be able to remove the ambi or right side. Attempt to install the new safety in reverse. It will probably require some fitting. If it engages and works properly then just leave it alone. If not, you will need to remove a small amount of material from the lug where it contacts the legs of the sear. Paint the area with Dykem Blue and try to install it. Move it as much as you can as if you were trying to engage/disengage it. Remove the safety and file no more than .003" from the "shiny spot". Repeat until the safety works properly. If you go too far the lug can be peened or stretched back out a little but as long as you don't take more than .003" at a time this shouldn't happen. George