I would not consider that truck for your purpose. Air ride as stated is not a good idea for off road applications, although the Pete 4 bag is better than the KW 8 bag off road, still not a great suspension for this application. I had a 4 bag air in a 378 Pete pulling a side dump. I don't like the short bed. Pulling a 160 with a tag trailer is a load. I would go with a 16' bed to max your payload on the truck and also to have a longer more stable towing platform. Although you guys on the East Coast can get by with less hp than we can, I would opt for more power. Your 160 likely weighs around 37K and your trailer about 10K, if you where to pull that kind of weight with that engine, I would want a lot gears. Although the 8LL is a good dump truck tranny off road, with this application of dump trucking and heavy over the road pulling I would not consider it.
I would look for a heavier spec truck, with a longer bed but that's based on my Out West experience which may not be completely applicable to you guys Out East.