Perfect antenna location on big trucks?

I use the both mirrors, antennas are high enough to be right about 13.5 so they can sing to me hitting something too low. Otherwise range is not that important Ive gotten out 20 miles regularly and 30 plus certain times and places where there is nothing around. The big challenge for me is hearing the #### thing so I use a external speaker near it where possible. It has saved lives because Ive gotten a timely message or really important information about trouble ahead.

I don't as a rule use it, it rides with the volume low unless I am number one in a convoy or caboose, then I take on the role whichever end I am on. Ive had 50+ trucks working together in out west during storms without trouble. So I know the set up works well.

The one time it really got important was the morning of 9-11, I was positioned in a high spot up near detriot and by default became a radio station of sorts. The people were good about it because they were in need of information as it developed live on our television and radio. that was a bad day. Im just glad I was not in the mid atlantic that day, the radio situation would have been impossible, a tower of babel with 100,000 truckers wanting to jabber.