▁Cad illa c ▁Se ville , ▁and ▁the ▁ 1 9 8 0 - 8 5 ▁Cad illa c ▁Se ville . ▁Mitchell ▁spent ▁the ▁entire ty ▁of ▁his ▁ 4 2 - year ▁career ▁in ▁autom obile ▁design ▁at ▁General ▁Mot ors , ▁eventually ▁becoming ▁Vice ▁President ▁of ▁Design , ▁a ▁position ▁he ▁held ▁for ▁ 1 9 ▁years ▁until ▁his ▁ret irement ▁in ▁ 1 9 7 7 . ▁His ▁design ▁ste ward ship ▁at ▁General ▁Mot ors ▁became ▁known ▁as ▁the ▁' B ill ▁Mitchell ▁era '. ▁ ▁Early ▁life ▁and ▁education ▁Bill ▁Mitchell ▁was ▁the ▁son ▁of ▁a ▁Bu ick ▁deal er ▁and ▁developed ▁a ▁talent ▁for ▁sketch ing ▁autom ob iles ▁at ▁an ▁early ▁age . ▁He ▁grew ▁up ▁in ▁Green ville , ▁PA ▁and ▁New ▁York ▁City . ▁ ▁Mitchell ▁attended ▁the ▁Car neg ie ▁Institute ▁of ▁Technology ▁in ▁Pitts burgh , ▁Pennsylvania ▁and ▁later ▁studied ▁at ▁the ▁Art ▁Stud ents ' ▁League ▁in ▁New ▁York , ▁New ▁York . ▁ ▁At ▁Bar ron ▁Col lier ▁Ad vert ising ▁After ▁comple ting ▁art ▁school , ▁Mitchell ▁joined ▁the ▁New ▁York ▁City ▁based ▁Bar ron ▁Col lier ▁Ad vert ising ▁where ▁he ▁prepared ▁layout s ▁and ▁advert ising ▁illustr ations , ▁including ▁U . S . ▁advert is ements ▁for ▁M G ▁cars . ▁While ▁working ▁at ▁the ▁ag ency , ▁Mitchell ▁met ▁brothers ▁Bar ron ▁Col lier ▁Jr ., ▁Mil es ▁Col lier ▁and ▁Sam ▁Col lier , ▁who ▁had ▁founded ▁the ▁Autom obile ▁Racing ▁Club ▁of