It is either a 70 or a 71. The 72's had the rectangular signal light in the grill. 70 had round signals in the bumper, and 71 were small rectangular lights in the bumper. I had a 70...and a (late) friend of mine had a 72.70-72 i think
I don't think the mid-80's Monte SS's had 350's. My (ex) brother-in-law has an 85 SS and its a 305 4bbl....I liked the mid-80's Monte Carlos, but not so much the Aerocoupe... Those 350's were SO easy to work on. You could mod those things up and make a ton of power with them.
The 80's SS monte was ugly as shit, the standard monte was quite good looking though. Buddy of mine had an 84 he did an LT1 conversion on, I'd take that over an uglier version with a 305 any day.