Does the Rubber Seal Around the Front Headlights Stretch?

Look, it's transparently obvious to most of us that 90% of what the body master is reported to have told you is false. In 10 minutes, you can verify or refute most of it for yourself.
Your writing skills indicate you are of above average intelligence. Learn to read, research, and verify. I told you I could shove a yardstick into the space between the headlight housing and bumper cover, no problem. So how hard can it be to go out with a ruler or plastic knife and see if you can shove the end of a towel in there.

The housings may have been hard to remove the first time, bucause the guide pins may be stuck in their rubber sockets. Once out, any body man worthy of the title would spread a dab of silicone grease on the pins so they would slide in and out like butter (lurkers: no sexual cannotations intended here).

I am not a mechanic and had never removed a Mustang headlight housing before 2 days ago. After doing some reasearch (reading the posts of others who have already done it), I did it just out of curiosity and to learn something. The wild claims from the body shop were simply too incredible for me to accept at face value. Egads! . . I even dared to remove it a second time to take the picture. No bumper scratches either time.
If you don't hava a 1/8" or larger gap between housing and bumper cover at the lens, the original cause you seek has been identified for you (the housing is too low or the bumper cover mounted too high).

Sorry for being so long winded.