First you need to measure what you have.
The measurement is from the wall, to the center of the drain.
If you measure to the center of the bolt caps, that should be close.
11.25" to 13.25" you would be using a 12" rough bowl.
13.25" or more, you can use a 14" rough-in.
The 14" Unifit will move the toilet back 2" but you need at least 13.25" to the center of the drain.