Tonight I ordered some valve cover gaskets and exhaust gaskets. there were no valve cover gaskets in the motor. im going to run the motor soon like tomorrow or friday, and adjust the valves. does anyone know the right plugs to run in a 455. i bought some that were 5/8 socket size and the ones i pulled out were 13/16. the 5/8 ones were loose when i took them out to check them, like finger tight..... any suggestions?