8ight-T center diff question

Hey guys, I have a few questions concerning the center diff on my 8ight-T. I would like too know if a 45t spur is usable with the Rc-monster mount and 14 and 15t pinions. Also will the plastic 45t spur gear from the 8ight-E buggy work with the smart diff? What about the kyosho spurs? I hope someone has the parts to test fit for me. Thanks guys.