I have a 70 Dearborn Boss 302, build date 12-1-69. The heater box diffuser has come loose from the top mounting point. I'm only guessing as there is no hole in the box at that location but would appear that there was once upon a time, a pin protruding from the box that the top mounting hole slide onto. Mine has two "push pins" holding the bottom of the diffuser in place. Anyone have a photo of the heater box that would show that area? Thanks in advance!