I don’t have a cab tractor, so my options are to put the GPS on my roll bar witch is almost a foot behind the rear axle or I am going to have to put it threw the hood which I only won’t to do as a last resort. So will placing the antenna behind the rear axle cause me grief?
no, just set the distance to a negative number. Easy.
In your case, -30cm or -12in depending on units
I ran the antenna wire down the outside of frame, to the front on top of the bull bar, it looks like an old radiator cap works great.
Do you have a canopy too or just the roll bar? Also you can sneak them under non metallic canopies, so you wont even see them. These small antennas are great. So many options.
Commercial AG GPS antennas seem to be overcompensating for something.