The screw on the left side should not be installed until the coverplate is in place. There is a hole in the cover plate for a long philips screw to hold the cover plate, radio bracket and mode control switch all together. Because your face plate decal is 1/4cm off, this may be enough to hide the hole for the longer screw to go. I bought a new mode switch diaphragm from PJ Grady, and it included a screw with it to replace the original one. It sounds like you may need this screw as the proper original ones were black and not stainless as you described. Walt Tampa, FL