I've been told the Mach 1 has the little half-a-moon slots in the back for the exhaust to come out. Looks like this. lol
That is one way I was told of telling.
| __ __ |
|_/ \__________/ \_|
------------------
1969 Mach 1, 351 Cleveland, 4 Speed. going threw a mild restoration.
Moving At The Speed Of Sound.
|