You're talking about the round scare/porch light right. Should just be screwed in. Simply unscrew and remove will give you access to the light inside. Not much to change besides putting in a different bulb/LED. Blue and amber seem to be common for those who do.
There are no screws on the outside. I tried prying and turning the bezel. No joy. I don't want to break or scratch anything. The owners manual is no help. As a matter of fact, I don't think the owners manual has been updated in a few years.
New ones must be different. Call the dealer you bought it from. By your location I'm guessing Colonial AS. Ask the service guys they're very helpful. Be sure to seal well when you put it back in.
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