Are you saying you "had" to notch the bores for clearance? Or did you choose to notch the bores for unshrouding purposes?
Newbomb Turk mentioned moving the valve center on the larger valves in small block heads. That is something I understand but had not considered on the Victor heads. Does anyone know if the valve center on the intake, or the intake and exhaust, were moved on the Victor small head? I have not seen that mentioned anywhere yet but they do say the heads were intended to use a big block style rocker arm and a 16 degree valve angle, so who knows.
The engine that Valley performance built with Victor heads supposedly used a 4.10" bore, so we know they "fit" in that bore size.