Hello all I'm new to this forum..so I'll just say I've read some of the things on here and was wanting to know the yr of all your cars. That being said I'll into duce my self as dennis "CARB",I've been researching and rebuilding .Q-jets most of my life....and cut to the chase....the green teflon stuff didn't appear till late 69 early 70.it was GMS way of fixing a problem with the throttle shaft and choke shafts from locking up.and to give a smoother action between parts.So if someone says they have a 66 GM with the green teflon Q-Jet 4bbl then they got it off something else.most late model Q jets started with a 170 number and some early with 654.....705....756...I have a Q JET here with no numbers anywhere..but looks like someone used late model parts .this carb has 13 screws.and are all standard head where some had Phillips and some have torx.but I restore more than just GM products. I research everything related to carberation.let me know if this helped any one .or if you think I'm just blowing stink ....but I'm the one that's been doing all this since 1996.yall have a great day .