Are you talking about the vent window seal or the door seals? Try taping the wing windows around the seal with some duct tape and do a test run. It should help you pin point where the noise is originating from.
I have had problems with the wing window hinge flexing so I don't open the wings anymore.
I remember back in the day both sides of the old man's K20 had folded match books under the wing window latches to keep them from whistling.
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Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help.
RIP Bob Parks.
1967 Burban the WMB,1991 S(stink)-10 Blazer,1969 GTO, 1970 Javelin, 1952 F2 Ford 4X4, 29 Model A, 72 Firebird. 85 Alfa Romeo
If it breaks I didn't want it in the first place
The WMB repair thread
http://67-72chevytrucks.com/vboard/s...d.php?t=698377