How To Replace Tail Light Unit On 2011 Rx450H

[fun33]

I cannot figure out how to remove the tail light assembly from the rear fender of my RX450h. I located and removed the plastic vent cover that gives access to the tail light assembly bulbs. I can see what appears to be four long bolts with nuts on them but access to the bolts is extremely difficult. Do additional panels need to be removed to access these nuts that appear to be securing the tail light assembly?