The CW 32 (32/32 - Motorcraft 740) and 32/34 should be good on a 235 (a 32/36 sounds interesting).

Either one would be too small for a 261 (and a 302), especially before the second barrel kicks in.

A single barrel 36 or 38 might be too much for a 235 - what are the CFM ratings for those carbs?