The factory book says 9Nm for everything except Speedmasters and they're listed at 12Nm. I think I I did 8-10 ft/lbs on mine with no adverse effect. It doesn't take much, you're just sealing the surfaces and trying not to warp the cover.
A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort. Herm Albright (1876 - 1944)