AirHeaded - Ah-8-Tee - Got ya back Pillion

I like to make sure my wife, my pillion, feels safe and comfy on the back of my bike.
So I have bought a Reynolds Backrest that fits the /6 seat (I think the seat is off a /6) I have fitted.
4 bolts and it is fitted. 4 bolts and its not fitted.
Love these old 70s parts.

I will have to make a pillion pad. maybe not as big as the one in the last 2 photos below.