1990 Mustang GT max rear tire size

Hi guys have a 1990 mustang GT has 225 60 15's right now. Want to run drag radials preferably a MT how wide can i go with out taking out the quad shocks on the rim and tire and how tall can i go with out and modifications.
What are you Fox body guys running??

Thanks in advance.
V

i would say 10inches wide and im not sure on how tall tho.