If you went with the 00 R calipers, you have to use the 13" rotors. If you want to go 14", you have a few options.
This was recently released by FTBR [like this week] and uses Wilwood calipers.
Cost right around $1400
The Fully Torqued Racing kits, with the exception of the original S197 GT caliper/GT500 rotor kit, use a rotor spacer to achieve proper alignment. This will push the wheels about 1/2" and is perfect for S197 offset wheels OR if you want a wider front track. Both kits fit most Mustang replica wheels but I was inquire with FTR, they have a will/wont list.
You can also PM me too see what I have sitting on the shelf that you may be interested in.