Not only was there opportunity, Jim, that was the norm! All the Pontiacs that I know of built in Canada used Chev engines, including the Beaumont SD, which a friend of mine has. All my Pontiacs, OTHER than my Firebird - which was built in the USA and sold in Canada, and the '70 GTO that I briefly had, had Chev engines. Only the GTO and Firebird had the "American Blue Block" as it was known up here.
Dealer installed anything to me is just one level above someone modifying the car at home, so that doesn't count as a factory car. It has to be an early Firebird or GTO with a Chev engine that was installed on the assembly line. Nothing else counts.
That's what this myth was perpetrated on, and that's what I want to debunk. And that's why I appreciate everyone's help with this, whatever the reason behind it!
I'm still tracing paperwork for the '68 Camaro OHC, which is even harder because of the lack of record-keeping on prototypes (development mules as Vikki pointed out) and of course the reluctance of Chev people to admit that Chevrolet suppressed Pontiac development of cars when it perceived a performance threat to their cars, especially their highest profile car. I don't pretend to know the motivations behind what happened or why John Poncho moved over to John Chev then finally to John Renault. I guess I shouldn't have spilled the beans so soon, looks like I may have stirred up a hornet's nest.
Vikki, I was going to do that but I think it might result in some hate email!
Q, the only GTOs I remember from that time was the '69 Judge that my uncle brought home that year and the '70 convert that I got a ride in one summer that had the "Tiger Button" - vacuum operated exhaust cut-out. I'll call some people, I didn't realize the "Jury" was from Calgary! I'm sure someone still remembers.