Can't speak to your particular boat but I had the misfortune of replacing an engine mount a few years back. The bolts holding the mount in place were lag bolts and from what I could see down their holes, the motor mounts looked to be a solid block of hardwood.
Made me think that I REALLY don't want to get water in those holes. I take particular care to ensure the tops of the lag bolts are re-sealed with silicone sealant each time I do an alignment. I've only had to do two small alignment adjustments in the 16 year life of the boat but I wouldn't want to make a regular habit of it. Be in for some really inventive thinking if you ever stripped one of the holes.