Its not correct for a first generation Camaro, but it actually looks similar to a late 60's Ford truck mirror! Donnelly furnished mirrors to other automobile manufacturers as well, so it may be for another GM division or even another company. Is there anything else stamped or cast into the mirror? You'll have to take it off the car to see the casting numbers inside the stem. More than likely the 2 DMI 8 signifies February 1968 because by 1978 Donnally was using an R in the coding (ie 2-DMI R-8), but it's definitely for some other model or company.