Just picked one of these up (correct part # according to their website) and in doing a dry a fit, I noticed that the diameter of the gasket (where the coolant/AF flows through) is smaller than the diameter of the outlet neck where it mounts to the block. As a result, part of the gasket rests on top of the thermostat. It's not going to block the AF/coolant flow released when the therm opens, but part of the gasket will be exposed inside the water neck outlet. My concern is the AF/coolant will disintegrate the exposed portion of the paper gasket over time and pieces of the gasket will end up in the AF/coolant and cause harm down the road. Should I be concerned about this or am I over-analyzing??

No, you shouldn't be concerned. Just trim it with a razor blade.

Didn't even think about that Jeff. Thanks for the guidance.

Don't do it. Don't use a gasket. Use some water pump silicone. I fought a leaking water outlet gasket for years. Tightening the bolts with a gasket causes the aluminum to bow and the gasket to leak. I haven't had a problem since I went without the gasket. Just my 2 cents, of course...

x2 Always use silicone based gasket maker. Gaskets just stick to the metal, poor sealing and awful to get off.

Thanks for the guidance Bob, I appreciate it. I did a search not too long about thermostats (trying to find guidance about gaskets, leaks, torquing, etc.) and I did see where you mentioned the same thing (fighting a leak for years and then going with just using silicone without the gasket). So if I go with just the silicone, am I right in thinking that I shouldn't torque the bolts to factory spec (which is 28-30 ft pds for the water neck outlet fasteners)? I would think that torquing to those specs would still cause the problem of the aluminum to bow.
The hard part is that I am noticing that there are a lot of differing opinions and solutions that have worked for many of our members on the forum (silicon only, gasket plus silicon, gasket only, Indian Head shellac and gasket, etc....). The good news is that deciding on which of the many solutions to use is good problem to have! Thanks again. I greatly value the input that I receive from everyone on this forum when faced with the same problem.

Yes, just hand tight. You don't want to squeeze out the silicone.

Makes sense. Thanks Bob.

No gasket. Just silicone. Apply to both pieces, install hand tight, let sit for 1/2 hour, then tighten down snug. Shouldn't ever leak even if things are a bit deteriorated or warped.

Thanks for the help Robert!