Yes, the rear tail lights can be switched, but not too easily. The panel behind the tail lights have a different depth between the years. So, if you were making a 79 into a 78, then you would have to use spacers behind the tail lights to make them flush like the 79 lights were. Also, the 78 tail light bulbes you could change from inside the trunk, but the 79 bulbs you had to remove the tail light to change the bulbs because inside the trunk was metal with no openings. Also, the rear end because of the sapcing difference the gas filler neck is also longer on a 79 than a 78. So again, if you were making a 79 into a 78, you would have to cut down the gas filler neck to fit behind the license plate holder. And yes, the bumper mounts were different.