I would say the height i have mounted the sensors is as good as you would get. Im pretty sure the height it is at would be similar to that of cars that have sensors from factory. But none the less i do get feedback from the ground only when im reversing the car out of the drive-way as the car goes on an angle and picks up the bitumen but only when the car goes on angle. I don't know or the exact words i would say is that i don't want to waste my time on giving you the exact angles and distance at which the sensors would start to sense. Though the sensors i have installed do sense a set degree of angle, i dont have the manual with me atm. But one thing i did was set the corner sensors so that it would also sense a bit of the sides as i you see the pick it is angled a bit so i had to do a bit of guessing work the best place on the bumper. But your question would depend on the sensors itself most have the same degree of angle i would guess, but should consult with the sensor manual first before starting to take measurements on your bumper.

And thanks for the complements guys, it gives me a sense of achievement in the modding community.

That's a fine lookin Ford dude!
Well done !

You already are old!

Well done asizzy!

NICE CAR MATE TOPS SORRYS ABOUT CAPS KEYBOARD IS F'ED