NPD has F150 cab mounts that consist of two different thicknesses in different positions. I'm guessing as no pictures are available, that the '78-'79 Bronco mounts don't consist of 8 of the same like EBs. Bmc69 has a good point, that a swap won't fit, so I'm probably going with frenchy's. They look exactly like what I had in mind and he assures me they work perfectly on EBs. He even Emailed a photo of his roadster, with the mounts installed, that has the right gap between the frame and the bottom of the grill. Poly body mount pads are equal to an aluminum puck in terms of absorbing sound and vibrations. I won't use them on the transfer case mount either. They work well as bump stops, sway bars, and shocks. Different materials for different applications.
My paint and body guy says he can bring the bottom of the grill down some if the gap looks too big. I need all the room under the hood I can get without having the look of a body lift.