well rebuilding the old guides with bronze walls is cheaper them putting in new cast iron guides. and if you are doing a job you mite as well do it right as half way. it cost no more in the long run.
i agree with ken on everything but the remark about using stones. i use stones and hold the runout to less then .001. i do all types of heads proformance heads for ford-chevy small blocks. inlines tractors.
