Some important info. for when you need to replace a tail-light bulb.

The entire tail-light must be removed.

1. Open lift gate, remove the 2 push-pins at the side, carefully (don't break them)
2. Look behind the light, remove the vent grill, carefully
3. Look behind insulation, you will see a black plastic wingnut.
4. IMPORTANT - stuff a rag in the hole below the wingnut, in case you drop it like I did.

Go to Dealership and buy a new wingnut ($8 CAD plus tax)***

5. CAREFULLY remove wingnut
6. Slide tail-light out
7. Replace burned out bulb
8. Installation is the reverse of removal.

*** Only if necessary

After searching on Google, I hear this is a common problem with Magnums and 300's.

One mechanic said he sprayed expanding foam insulation in his car to block the hole so he doesn't lose his wingnuts.