You apply the bedding compound...Devcon Marine Tex, what ever- tighten the screws down while checking the with a straight edge and let it cure.....then after it is cured torque the screws to the proper setting (15 inch pounds) and you base is straight, tight and stress free.
Very good solution, beats machining. Have you ever had the epoxy (I like the K-poxy titanium) get on the screws? Some epoxys have an affinity for oils or silicones.