The waterways are very close but if using the correct stud, tightened up to the correct torque with the correct loctite they shouldn't move on tightening, but often will come out when undoing them.
The way to get it to stay put is not by over tightening the nut, make your own locknuts, I've never had one come loose on any car in 30+ years, inc ones used on track, only takes a minute to make as well.
If the sealant doesn't work, and I suspect it won't due to the heat around there, try some Kalimex K- Seal.
tabetha