While replacing the window channel felt on my 55 Olds 2dr, I found the adjusting screws at the bottom of the window channel were different lengths on the right and left door. One is 1 7/8 inch long and the other is 2 1/2 inches. Is this correct? Does anyone know of a source for this part and if not, would a part from another GM car fit? Google search for the Olds part keeps directing me to tri-five chevy part suppliers.