[camr]

Did you check the bolt torque? It should be around 60-75 lbs./in. If they still leak, try a set of Ford Motorsport M-6584-A50 rocker cover gaskets. Steel core with a bonded o-ring on each side. Ford used these in production towards the end of the 5.0/5.8 run because they solved a lot of leak issues. They can be reused, too. If you have an old Roush engine with the plastic plug wire looms under the valve cover bolts, get rid of 'em. They now use billet aluminum pieces that allow the bolts to hold torque far better and they look a lot nicer.

Hope this helps.