tmanmi

New member here. I have done some searching on the site but haven't found what I am looking for. I got a little to close to a mail box and cracked the back plastic cover on my passenger side towing mirror. The cover was the only thing damaged but GM says can't buy parts, just whole mirror. I found a damaged one on ebay with the cover intact. Anyone have any links of videos of how to disassemble the mirror to replace the cover?