SSEBONNE4EVA, I'd say you are "right on." I sometimes get the very real feeling that that HUGE GM GIANT has no real care or concern at all for the majority of their long-time faithful customers. ESPECIALLY the used car customer.
EVERY SINGLE TIME things like this come up, and I go out of my way to visit with and share our knowledge with Dealership people, -especially those in the parts and service departments, I AM JUST WASTING MY TIME.
The feeling I get is that GM only cares about selling as many NEW CARS as they can. And only when are they FORCED TO, do they come up with a cheap "bubble gum and duct tape" patch to get the car through the warranty period. And after that period is up, quite frankly they just DON'T GIVE A $#@%
Essentially they NEVER ADMIT any guilt.
But what do I do, (talk about stupid) I keep on buying GM "H" cars. -like the 2002 SE that I have spend untold hours on already fixing GM design screw-ups. (at least with most of the GM messes, I'm able to make "home garage mechanic" repairs, unlike some of the horror stories I hear about other manufacturers, with things like bad transmissions, engines, etc)
Say, on the dimension of the EGR parts, please see Bill Buttermore'* thread on his "low cost EGR tube." I have a reply there that give the dimensions. And when I get my Brother'* LaSabre apart in a few days, I'll reply to that same thread on what I find there.