It could be a Bel Air or a 210. The front bumper is definitely from a '57 but the lack of tail fin and side molding is like a '56. If I recall the front clip of a '57 will bolt up to a '55 through '57. What do you think?
The molding includes a dip BELOW the prime center mold, which is not on any of those models. Cannot find it on the other makes, either (my gut was Pontiac), which makes me wonder if it is slightly customized, tragically already.
I do not know enough about the cars to say anything about easy interchangeability!
There are elements from several mid-50’s GM coupes on there, with the “base” of it all being a ‘56 Chevy, imho. The grille area has a little ‘55 Oldsmobile going on. Appears to be heavily customized using mostly stock GM bolt on chrome bits on a mildly channeled body, but some of it was created one-off because it doesn’t appear to have come from any other model.
BTW, that nose of the hood bothered me from the start. Looks too blunt. Another thing that made me think “been customized”.