Are we talkng about a GMC COE, & a Chevrolet COE ? If so, that was one of the evident differences in the two makes. If not someone in the past, made the improvement. All '47-'55 1st series GMC COE's have there air cleaner under the hood with the throat of the updraft carb. facing forward. On a '47-'53 Chevrolet COE the air cleaner is under the cab floor as Lightholder's Dad mentioned, with the carb. throat facing the rear. 1954, & '55 Chevrolets were the same as the GMC's. I've changed the carburetors, & air cleaners on two (a '51, & a '53)Chevy COE's, to get them from under the floor.