camaromikey, the part number (3957203) won't be found on the mirror. However, 9-DMI-9 indicates a date code of September, 1969. 14-2269 and 15-2270 I believe, are the correct casting numbers for a 69 Remote Mirror base and head, and 3958372 is the correct bezel for a 69 Camaro with Standard Interior. HOWEVER, these same numbers may have been used on other models and/or years as well. I know for sure the Bezel was also used on the 70 Chevelle, so you might have a mirror for that car. My books don't go up that far, so maybe someone else can give you more info.
You do know that the mirror can be adjusted, right? Loosen the screw on the back and adjust as necessary. If it's still wrong after that, you probably have the wrong mirror.