I have your RHS Pro Action aluminum heads with the 5/8" threaded hole for accessory mounting. The heads are on a Ford 302 block in a 1968 Mustang. I am wanting to use the stock alternator/brackets and bolt. The pivot bolt is 7/16-14. I need a threaded insert for the head's 5/8-11 hole. Do you provide an insert or can direct me to a source for the insert. Thank you for your assistance. Michael