Seacock sealant squeezing

A bit late but I use silicon sealant fo all my underwater fittings. The trick I use is to tighten up, then leave for the recommended curing time before hardening up. The sealant I use is Fernox LSX. Only my deck fittings have ever shown any problems and even then it's mostly the stanchion bases.
 
There's lots of well-experienced guidance above, so I don't feel guilty about introducing just a tad of thread drift.....

Which is messier? CT1 or Sikaflex 291...? I already know which is cheaper, and doesn't go off in the tube.
 
Messiness is largely the responsibility of the operator. For skin fittings easiest way to avoid mess is to mask off around the hole in the hull, apply your ring of sealant around the hull (not easy upside down!) put a ring around the thread at the root and push in. Tighten back nut, leave to cure and cut off the surplus around the fitting.
 
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