I believe that in general, the head is torqued down onto the metal head gasket to such an extent that you don't need (or want) any sealant. All you need to do is make sure you have clean shiny (and flat) metal surfaces.
Not so easy to determine flatness, but if you have no reason to suspect warpage it shouldn't be a problem. If you had head gasket leakage it may be an issue - I think most people have a shop determine flatness in that case. Your block probably won't warp.