dude, dont worry about taking it off, you have 2 screws to mount right, or is it 2 bolts, if its 2 screws, dont bother drilling, it will weaken the setup, just screw the bracket in, then bolt the tach onto the bracket, voila u have urself a tach, plz say its not a 5" monster tach, please tell me u got a smaller one lol
unless ur going all out drag