Sounds like safe bet is for Tony1968 to get to do some homework... if he can compare or confirm the existing cylinders and replacement ones are the same (so we know rod compatability) then if he posts a pic of the new cylinder he's gonna use we can try to match itHahaha! Confusion creates the chaos!
I have NO earthly idea who started all this baloney. All I can say is be careful and take pictures of sh*t you take out of your door. Apparently GM decided they were going to change stuff up often for door lock parts. And then the fuggin' things don't work well after a while anyway. You would think the changes would make them better...but NOOOoooooo.