Does the 69 GT500 have the hood to cowl and the hood to radiator seals?? Anything required to attach them?
For the radiator support does your car have the original one? if so it will provide a clue to how the seal there would have been attached. Look for pairs of very small holes in a pattern along the top rear edge. If not there the radiator support was changed out at some point or the guys at the plant were having issues with the stapler that day and they used the metal clips instead
As for the rear hood seal the seal slides into place along the forward lip of the cowl cover