Hey, thanks for the great information, Raya!
The point about bedding is critical for reducing leaks
, I need to go there.
The chart posted gives good descriptions of several product families, I've tried a calk from Wurth which is incredibly tough. I'll post the name after I go find the tube.
The one good thing about silicone sealers is they have almost always been just spooged over top of the component or flange. When the removal, prep. and re-bed procedure Raya describes is followed that oily residue is mostly away from this bedding area.