Use those UniStrut channels with rollers combined with a fairly lightweight bypass door system. When open you would have a half open wall and front. If you want even more make a three or four bypass which would stack the doors and open it up. A square frame of 2 x 3 sheeted with 1/4" ply on both sides will make a stout but light door. Really be a help in winter keeping the mill dry as possible. The roller assemblies are pretty cheap and make it a quick job. You can get three tracks side by side on a 2x6 (1 5/8" wide each).

PS: Those rollers can be run right off the end of the tracks so the 'walls' can be completely taken off in the summer if desired. Also they make a container that is called a 'high cube' which gives nine feet of headroom so a pitched roof can be easily made without losing headroom. Just FYI for your next container. A good idea to extend your roof over the container as they often leak which is why they are sold off as they age.

nice job as always👍 that slash in the front left tire not good.

What model Croc are you running these days?? Those puppies look nice!