The valve guides are not removable, they are an integral part of the cylinder head. Any cutting or grinding operation performed on the valve guides, should be done by a qualified machine shop.
valve guides which are not excessively worn or distorted may, in some cases, be knurled. Knurling is a process in which metal is displaced and raised, thereby reducing clearance. Knurling also provides excellent oil control.
This procedure should only be performed by a qualified machine shop.
Fig. Critical valve dimensions
Fig. Checking the valve stem-to-guide clearance
Fig. Cutaway of a knurled valve book