I wish it was easy to model a vehicle. I have done some testing with a friend. My puck mount preformed as good as a mag mount with a counterpoise..... Im starting to believe antennas being 6' off the ground really dont make much difference in mounting. I have also done blind antenna testing (on a hilltop) switching multiple antennas many times. The winner...... A 5' Firestik....lol I give up what ever tunes works for me!!!Performance will be proportional to the size of horizontal metal mass directly at the feedpoint. Center of roof should perform 20 times greater than top of roof rack or headache rack.