If the press is any good, and has a decent heat platen, it should easily press an area 1" smaller. The platen should be the same temp edge to edge. I go 14" on my antique 15" Insta when I need to.
Though not accurate for actual temp (due especially to the reflective teflon coating), a non-contact gun should be able to give you an idea of this.
And yes, as you can see, I split this off to its own thread. Certainly not Brad's introduction any longer, lol!