Both for this tool.. the height for retainer clearance and the outside for the non-stock type of seal. If you don't want the different seals, I suppose you could just grind down the guide tops a bit with a grinder... not what you want to do 'on-engine' however! And there are several different tools available.
Spring seat cutters are different:
http://www.compcams.com/catalog/COMP2012/pdf/COMP_Catalog_2012_362.pdf
Got those heads off yet? Inquring minds want to know....
