Well, the peppermint oil seems to work. I put peppermint-oil soaked cottonballs in the cabin and no sign of incursion there. I also placed a mint soaked ball of cotton in the starboard vent line. I noticed today rat droppings in the engine compartment behind the stuffing box, but the varmit apparently couldn't take the scent of peppermint and chewed his way through the port vent line and vacated the premises. At the port vent outside you can see little black footprints coming out the vent hole, and I placed another cotton soaked ball in the port vent. If anybody else is still in there they are very uncomfortable and will find a baited trap awaiting them at the foot of the companionway stairs.