How to tell???????

I decoded my 67 Cuda Vin# and it is a 273 2v with either 180hp or 235hp. How can I tell which. Also, What is the most likely automatic transmission in the car? If it helps, is is single exhaust with the floor console shifter and power steering. I need to decide whether to build the 273 or change to a bigger engine for street/cruising use. Would appreciate some input.
Thanks, Rat