set up for BL revo.

hey guys im new on here. and my friend has made a bl hyper 7. so im going to try and convert my revo to bl. i was thinking of using a feiago 9xl for the motor, but the esc, i dont know to much about, but i want to spend and little money as possible, so cheapest is the best :). can i use the stock spur gear and tranny? do i need a mod 1 ( i think i do, but which one for stock spur). and any other info you can help me out on would be apreciated. (this will be my build thread also) .