i think i like this idea better
I'll build a 90° bracket and use 2 8mm bolts to attach it to the upper driverside corner of the back of the cab. I know the reception is best when you get the antenna up off the ground
but it's your truck
and i'd use 3 bolts in a triangle
they sell verious springs, say light duty and heavy duty, just get a heavy duty one and the only time it would flop over would be if say it hit the roof at the drive threw or some branches