I put them on my buddy's 87 GN (stock valve covers). No trimming necessary. Just lay them on the heads, bring the valve covers over the top, and run the bolts in.
The proper orientation is stamped on the gaskets. They are to be installed dry, no exceptions. Proper torque is also stated. They do have torque limiters. FWIW, Strezo recommended them to me. Really nice gaskets if you ask me.
strike