[pat in Santa Cruz]

They should just push in place. Drop the valve in the bore, place the guides around the valve stem and push up. If they do not fit, possibly the bores are dirty. Unless they are exactly the same centers as the old ones, I would think the seats now must be re-surfaced to be concentric with the new guides.. I always end up having modern guides and valves put in. They're good quality American valves. If the original guides are so worn, the stems probably are too...might as well do the whole job the right way and be done with it. Its too much work to have to repeat it any time soon.