RothcoAcrylic Commando Sweater GI Style Military Sweater

Is there a way that i can trim the end of this sweater myself? Its way too long and id like to know if cutting it with scissors will ruin it.

Do they run true to size? I’m a 2xl long. (6-5 250)

I am 6' 200 pounds. What size is recommended?

Can you please recommend the size for my shoulder size 18 inch