</s> ▁William ▁L . ▁Mitchell ▁( J uly ▁ 2 , ▁ 1 9 1 2 ▁in ▁Cleveland , ▁Ohio ▁– ▁September ▁ 1 2 , ▁ 1 9 8 8 ▁in ▁Royal ▁Oak , ▁Michigan ) ▁was ▁an ▁American ▁autom obile ▁designer . ▁Mitchell ▁worked ▁briefly ▁as ▁an ▁advert ising ▁illustr ator ▁and ▁as ▁the ▁official ▁illustr ator ▁of ▁the ▁Autom obile ▁Racing ▁Club ▁of ▁America ▁before ▁being ▁rec ru ited ▁by ▁Har ley ▁Earl ▁to ▁join ▁the ▁Art ▁and ▁Col our ▁Section ▁of ▁General ▁Mot ors ▁in ▁ 1 9 3 5 . ▁ ▁Mitchell ▁is ▁responsible ▁for ▁creating ▁or ▁influen cing ▁the ▁design ▁of ▁over ▁ 7 2 . 5 ▁million ▁autom ob iles ▁produced ▁by ▁G M , ▁including ▁such ▁land mark ▁vehicles ▁as ▁the ▁ 1 9 3 8 ▁Cad illa c ▁Si xty ▁Special , ▁the ▁ 1 9 4 9 ▁Cad illa c ▁Coupe ▁de V ille , ▁the ▁ 1 9 5 5 - 5 7 ▁Che v ro let ▁Bel ▁Air , ▁the ▁ 1 9 5 9 - 1 9 8 4 ▁Cad illa c ▁De V ille , ▁the ▁ 1 9 6 3 - 6 5 ▁and ▁ 1 9 6 6 - 6 7 ▁Bu ick ▁Riv iera , ▁the ▁ 1 9 6 1 - 7 6 ▁Cor v ette ▁St ing ray , ▁the ▁ 1 9 7 0 - 8 1 ▁Che v ro let ▁Cam aro , ▁the ▁ 1 9 7 6 - 7 9