Hi, new to the forum here. I have been reading up on seacocks and thru hulls as i will be replacing them on my new-to-me Hunter. I am familiar with NPT threaded fittings which form a seal by interference between the two parts, with some help from a lubricant or sealer. And also that we shouldn't force NPT female threads onto NPS male threads and hope for the best. What I can't quite see is, if a "proper" thru hull has NPS male theads, and a "proper" seacock has NPS female threads, where does the actual seal take place? Reading the installation instructions that Groco for instance publishes it is not clear what seals the NPS threads. The instructions call for the installer to shorten the thru hull to 1/4" less than the full threaded depth of the seacock. So the seal doesn't take place there as it does with some hydraulic fittings (JIS for example). Apparently the inboard end of the seacock is NPT, so easy going from there. Are the NPS threads t be coated with a sealer and ther eis no actual mechanical interference fit?