Access to remove outside mirror RX450h
 

I need to remove and replace my outside mirror. It looks like there is a small triangle shaped black plastic cover in the corner of the door that would give access to the mirror inside attachment?
Can anybody confirm that this is the access point and that this cover can be snapped out?
thanks, R J Coupe.

R J, welcome to CL. The mirror can be removed without taking the door apart. Check out the first few pictures in this thread.

Thanks Anita: That was a very detailed tear down. I may need that info in the future. My problem is that I have to replace the whole mirror assembly. I need to access the base of the mirror mount from the inside of the door. it looks like a small black plastic cover inside next to where the mirror base attaches is the access point. I want to make sure before I try to pop it off. I don't want to break another part. The $600 mirror assembly was enough.
R J coupe

I am pretty sure that the panel you want to take off is inside the car. Normally you have to take off the inside door panel to access the screws that hold the mirror onto the door. From the pictures I have seen the mirror has studs that go through openings in the door/window area that you put nuts on to hold in place.