I installed a few safety pins to make SURE the rear body section of my black Mirage will not come loose at high speed-- remember what happened to Bruce McLaren. I've see a picture of one that came unlatched at just highway speeds-- not pretty; did lots of damage.
The sides of a Mirage rear body have molded- in indentations for quick- release pins; Manta Cars installed them in their factory demonstrator MANTA 2. To take advantage of this method of rear body fastening, a vertical piece must be fabricated and bolted or welded to a side- pod chassis tube so that the pin has something to slip in to. Make the depth of the piece such that the quick- release pin balls pop out to lock it into place. I used 1/2" diameter pins made by Hartwell-- more surplus stuff.
A second piece of insurance is the pair of "hood pins" that I installed on the top of the rear body. The 1/2" aluminum pin bolts to a steel bracket welded to the rear hoop of my roll cage. This came from Speedway Motors. Since the rear body of a Mirage is hinged at the rear, the front closes on an arc rather than straight down; this made it necessary to angle the pin slightly backward and make the hole slightly oval to accommodate the arc.
These details make the rear body mounting very solid and safe. I thought these photos might help explain how they were mounted-- sorry about the poor focus..
Look closely at your car-- could it come loose? If you have the least doubt, install some extra safety pins!
Regards, Neil Tucson, AZ