Sports Mirror Fitting Instructionss
I understand that Sheets 18 and 19 of the AIM have this information (pages 254 and 255). These were posted on this forum a while back, but I can't find them anywhere now.
Thanks in advance.





just a crazy idea to save time in the future, maybe buy a copy of the AIM.
Last edited by 4-vettes; Jun 5, 2026 at 05:55 AM.
Its more involved that just swapping the mirrors which was what I thought before I got into doing the job.
One of the issues is drilling the holes in the door.
Another issue is drilling the holes through the metal door frame big enough to install the nuts but also big enough to pass a socket to access the nuts.
Depending on the washer size attached to the nut and the diameter of the socket I’m looking at having to drill 9/16” or 5/8” holes in the metal door frame.
Besides the mounting holes in the fiberglass you’ll need to bore a large hole to pass the cable adjustment assembly through.
It doesn’t come apart so don’t even try.
Another issue I found was that at some point GM changed the mirror mounting studs from SAE to metric thread and I had to locate metric washer spinning nuts to fit the studs on my later model NOS sport mirrors.
Several vendors sell the free spinning washer nuts but they don’t specify 1/4-20 or M6-1.0 threads.
You will need to remove the window glass to drill the holes and mount the mirrors.
I actually have two threads covering what I need to do and the multitude of questions I’ve had to ask.
There are also several good videos you can Google to help you out.
These are the M6-1.0 threaded free spinning washer nuts I found that fit my sport mirrors.
They are a GM nut used for several different make and model GM cars and trucks.
Here are another set of mounting diagrams that were from Wilcox.
Last edited by OldCarBum; Yesterday at 01:30 PM.
The gaskets between the door panel and the mirrors must be mounted with the thick side towards the top.
If they are mounted wrong the inside edge of the mirror is too close to the window and may interfere with the window operation.
There is no left or right side specific gasket.
Here is a picture from the 77 AIM that shows some additional details regarding the hole placement and sizes for the drivers door.
Last edited by OldCarBum; Yesterday at 05:21 PM.
There appear to be two options for the vertical positioning of the mounting holes (relative to top of the door skin) - either through the upper metal door frame, with nuts attaching the mirror onto it, or, through the fiberglass below the metal frame. In the latter case, a backing plate would be needed to spread the load and prevent the fiberglass from cracking with vibration. The AIM diagrams showing the positioning 1.55" - 1.60" below the top of the door panel, seem to suggest drilling through the metal frame.
Interestingly, there is no information suggesting the fore and aft positioning of the mirrors. From my setup trials, I think that a position about half way between the original mounting location of the old blade mirrors and the front edge of the door panel seems optimum.






