I sat straight up in bed about 2 a.m., and couldn't believe I had read this.. "grinding the drain hole."
You DO realize all the lifters can be removed thru the upper openings in the head, without the need for any grinding.! !. Pull the lifter out the bore and out the opening, install is reverse. Intake removal not nec.
Sometimes a stock length intake bolt needs loosening a coupla turns.. no grinding..
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