Replacing the valve guides and cutting the seats is a job for the machinist, the right tools & experience. If you stay stock type replacement valves, they can be had in oversize
stems, & the guides are reamed/honed .005" or .010" over to accept them. If you replace or resize the guides you will automatically need the seats re-cut........& no, don't let
someone talk you into knurling & reaming the guides.
