I am trying to match existing door profiles in a residential project. The existing doors have wider stiles and rails then what I am finding in rated 90 minute door profiles. Can I order a 90 minute flush door and add 3/4" wood "stiles" and "rails" to one face of it without voiding the rating? This wood create a thicker door and I just want to be sure adding to it will not nullify the UL label. Thanks in advance.