delta76
First off, be very careful!! When i read the thread title “plumbers silicone” my head immediately went to “sealer”.
Fernox LS-X is NOT for the orings and flow control! e.g. the last time i used it was to plug and seal the drain valve on the synchronika. the ball valve was bypassing and it was easier to plug it than to replace the valve at the time. (and i didnt have one to hand!!)
Theres a big difference in Silicone Sealer and Silicone Lubricant. for your current needs you do not want sealer and sorry if my reply confused rather than helped.
also you will see many Molykote numbers, 111 being to popular go to for group head rebuild. Be careful when ordering!!