Bill Leska wrote:

Thanks for the advice. I shouldn't have to add anything to the floor, since
the slab is under the carpet.

But if I pull the toilet and tile up to the flange, will the toilet still
mount on the flange, or do I need to somehow pull the flange out and build
it up, too?

SNIP

Since you'll only be adding the thickness of a tile,
you can leave the flange where it is and double up the
wax ring or use a "flange extender" (like a plastic shim).
Use enough wax or whatever so that the wax ring will
compress about 1/2" to 3/4" when the bowl is set.

The bowl may not sit evenly on the tiles. If it rocks,
shim it (I like thin rubber gasket material) or set in
grout/plaster or caulk. There are as many opinions on
this as there are Usenet users...
Do a GOOGLE Advanced search.

Jim