The trimmers can be disassembled by sliding the retainer to one side. The top section that turns will have some silver material which has been transfered onto the bottom surface. A q-tip with some De-Oxit will remove the plating that has rubbed/scrapped onto it.
Indeed, I was able to bring three dead rf cans back to life by disassembling and cleaning the trimmers. On one of them I broke the coil wire so it lost a couple turns when I fixed it. It aligned fine though.
Thanks for the good advice, the alignment is done!
Rich