Bob, are you going to use any coatings besides the rocker arms. If I ever get my engine assembled I had planned to have the intake manifold coated as well as the combustion chambers. The email I received from Polydyn said the most bang for the buck was to have the crankshaft coated.
Check out this old article on old school improvements:
Old-School: $11 of Mods + New Tires = 25% Better Fuel Economy : TreeHugger
Harold