Technical 53-54 Poncho similarities

I'm in search of a solid/semi solid 53 pontiac catalina body but have more luck finding 54's. Besides drive train and the obvious differences in trim and interior was wondering what, if any, is the differences between the 53 and 54 pontiac shells?

 

IIFC, the drivetrains are the same, as are the frames, body shells, glass, doors, fenders, yada, yada. The main exterior difference is the grille (you can google pics). Not sure about the dash and gauges. They are damned near twins.....