Would that NVH be the 1/8 in. thick foam like sheet of stuff on the stiffener? Is that adhesive on both sides? Where can you get it?
Nope, that's not it. There are different types of NVH. You want anti-flutter for the part attached to the outer part of the quarter. You should see what's left of it when you took them off. The inner part gets spot welded. Or in your case plug welded with the option of adhesive. Your jobber has these products.
Read this: http://www.bodyshopbusiness.com/Article/82136/guide_to_adhesives_in_collision_repair.aspx
There are numerous articles pertaining to many products in the field. If you want to know more go to Refinish Network also. It's geared predominently to pros and shop owners.
Scott - Would this be considered factory or after market install (Van Nuys Plant)?
I cannot say with certainty from that photo. Against my speculation rule I'll say yes. Look on top in the gutter area, You should see clean evidence of STRSW's (Squeeze Type Resistance Spot Weld), and the run number in the corner. Most shops do not spot weld again, they plug weld. Basically any evidence of non factory welds on all pinchwelds. There may be globs of sealer stuffed in the rear of the quarter at the tailpanel/quarter pinchweld. Sometimes there's a finger or thumbmark in them. I know, hard tellin' not knowin'. You notice all this BS when you take one apart, if your curious while doing so that is.
I see you added another photo. That left side looks original. No evidence of plug welds. Both sides are crusty looking and typical factory paint pattern. No way to tell what may have been done to the rest of the tin like the lower part of the qrtrs.