mounting omni 2.4 in middle of tower


I need some advise we are mounting a 2.4 omni at 200ft which is the middle of a pipe tower. What is the recommended distance from the tower leg. I have read anywhere from 6" to 5’ Could really use the help?


I have just recieved it strait from last mile, a min of 30" but would prefer 48" off the tower leg.