On the 71-3 Mustang fastbacks, looking thru the almost flat rear glass was quite a challange, much worse than my 69 & 70 Mach 1s, or my 69 Cobra fastbacks. And with the wider body, tall dashboard , and low seating position, seeing the front and sides of the car was also a chore. Back in 76, I test drove several different cars at a local performance car lot, including a 71 Mach 1 351C 4 barrel 4 speed. Compared to the 70 Mustang Sportsroof (351C 4 barrel with Shaker), that I ended up buying (for $2100. , it was great time for buying late model cars!), that 71 felt like I was going to be clipping parked cars on both sides of the street at the same time, it seemed so wise. And looking out the rear view mirror was like looking thru a mail slot.