Once you've worked with butyl tape, you won't want to go back to messy liquid sealants.
Life Caulk is the devils-own invention, very runny, hard to remove - I can say that because I used it to seal my rope clutches!
I make my own backing plates with s/s plate from McMaster Carr. Finished job looks like this (4-way Garhauer rope clutch)
S/S has a reputation for being hard to work, but I did this all with ordinary tools - jigsaw with HSS blade, files, sandpaper, power drill with carbide bit.