Was wondering how often Tahoe / Yukon owners are encountering factory original parts with no part numbers? How common is that? On my 2007 Tahoe I've been frustrated by not being able to find any part number or reference for the rubber flap guard which protects the ABS computer in the undercarriage, as well as the little 1/4 twist knobs which hold the "storage cover trim" compartment cover in the rear interior driver's side where the jack is stored. The door doesn't come with them, and the only other way I can see to order them is to find the entire inertior panel of that wall which they are mounted in. I subsequently went to a junkyard to get a twist knob out of a another Tahoe. Still nothing on the rubber flap for a part, not sure where / what to use as a replacement.