setting toilet bowl in horned wax ring over tile floor

I mispoke when I said that the the 3" spigot flange went into a 3" pipe. It actually goes into the bell/hub end of a 3" fitting. Thus the inner diameter of the 3" spigot flange would nominally be 3" but due to a ridge where the knockout was attached the inner diameter of this flange is just slightly larger than 2.75". I paused slightly when I was saying that because I realized the dimensions I was quoting were not consistent with a flange going into a 3" pipe. sorry for the confusion there. If that flange had gone into a 3" pipe it would not be called a 3" spigot flange and it would have a smaller inner diameter and the horned wax ring would not have fit.