Does its bum look like this.
All the FFR Coupes Ive seen run a rear spolier that is riveted on not, part of the body itself. The Daytona Sports Car Coupes dont' as they are all part of the body. Harrison's from memory are also moulded on.
The bonnet bulge while easy enough to change is alot bigger on a DRB. But the DRB also seems to have a moulded on rear spolier. Does your car have a recessed spot for the rego plate like this one? (This one is a DRB)