April 26th is the change over date on the Lucas lights. If the car was built before this date, it would be correct with either Marshals or Lucas. If it was built on or after April 26th, Lucas is the only light correct for the car. Marshal fog light brackets were left in place as the grills were already assembled.
When you put the Lucas lights back on, make sure the pedistal holes are drilled in the correct spot, and use the correct mounting hardware, High Country Bob can probably help you out with that if you don't have the original pedistals. (Keep in mind during the recall, a lot of dealers didn't know how to mount the lights, and they ended up on the square mounts, and not the round pedistals which lifted the light to the center of the grill). If the Fog light brackets were damaged, you can get real quality brackets from Delta Bay Mustang in Pittsburg, Ca. They are about $70.00 a pair, but are correct.
Good luck. Mike