#1. Agreed. And that was the key to disproving this myth. Vikki steadfastly maintained this from the outset and was 100% correct.
#2. My source's statement that ALL Canadian Pontiacs were built on the appropriate Chev chassis and with Chev drivetrain coincides with my personal experience. I'd question the "smaller" part of George's answer as well as the 302 part. To my knowledge, the 302 was a Camaro specific option - Z-28 only I think. 307s were certainly common enough in the early '70s!
#3. By the '80s and '90s, GM plants on both sides of the border were using engines produced by the different divisions without regard to the car line that they were installed in - the Corporate engine scheme. Chev provided 60 and 90 degree V-6s (2.8/3.1/3.4 and 4.3) and the small block V-8, Buick provided the 90 degree 3.8 V-6 and Pontiac seemed to be producing only four cylinder engines.
#4. Chev engines were put in Camaros that were disguised to look like Firebirds! And yes there were a few Firebirds that did receive a "Heartbeat" transplant before the Pontiac 303 hit the scene, but those were by racing teams, not for sale to the general public at any local Canadian Pontiac dealer!
#1 is the key as mentioned, and sounds the death knell for the myth.
