The right hand parking/tail light is fuse #3 on my 87300E - a white fuse. Sometimes the fuses look OK, and sometimes even test out OK, but occasionally have a hairline crack or corrosion which causes intermittent failure.
Is the bulb OK, does switching the right hand and left hand bulbs make any difference? Do the other things on that fuse work OK - License plate, headlight wipers, etc? If the fuse, bulb, and everything else on that #3 fuse circuit are OK, I would check the headlight switch. Do the standing lights for the right side come on when selected from the dash headlight switch?
If it isn't the switch, some people have reported corrosion under the fuse box is possible where wires join the fuse contacts. You could run a wire outside the car from the fuse contact to the bulb and see if it is a wiring problem.
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