I have a 99 528i and recently the inside of my headlight started "bouncing
around" whenever I go over the slightest bump.

I inspected it and made sure the lamp is installed properly and it is.

Do you think it's an adjuster that went bad?

I saw some postings on other forums and they talk about having to heat up
the headlight to remove the clear plastic to get to the inside.

Do I need to replace this part or is there a poor man's way to deal with
this?

Jeff