It will be painted black, but you will also find a lot of clips and holes that attach the trimwork to the sheetmetal (as well as adhesive tape). I have looked for photos of someone taking this plastic trim off of a LX470, but haven't had any luck. If you take yours off, please docuement it with photos.
I am wanting to take mine off my LX permanently at some point, but then I need to address the hole issue. Maybe Bondo and refinish? Not sure... If you are not taking them off permanently, you will have to get more adhesive tape and some clips in case some break during removal.