A standard M1 carbine with or without the bayonet lug is fine under MA law and isn't an AW unless it was (highly unlikely) fitted with a flash hider and bayonet lug on 9/13/1994.
As I was futilely trying to explain to someone else in the Firearms forum, with a CMP carbine, it's absurdly easy to prove that the firearm was not in paratrooper configuration on that date because the Italian carbines that are being sold now were put into storage in standard configuration before that.
The paratroopers that CMP will be selling are a different matter. Those were used by the Greeks and were in that configuration prior to 94 so they should be OK.
In short, converting a standard M1 carbine to paratrooper config in Massachusetts is illegal. kthxbye.