They have an allen hole in the top. But you will need a deep 12 point socket. You can pick up a full set of craftsman metric and SAE at OSH hardware for like 14 bucks. You might need to modify the inside of the valve cover in a place or to. It's no big deal. Just put some grese on the top of the stud and put the cover on. Where the grese sticks to the cover just hit lightly with a grinder or somthing. I did it to my first gen.
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