Nice construction job there
May I suggest though that in order to *preserve* your nice construction job, before attaching anything solid to the upwind sides, you might oughta get some diagonal bracing in there, particularly in the direction of the prevailing winds. Otherwise it is very likely that your whole run assembly is going to start going all cattywhompus and becoming whatever you call the 3D version of a parallelogram (as opposed to the rectangular construction it is now).
It's real easy to do, just stoutly screw a few 2x4s on the major diagonals of all walls. Most important are diagonals going from high-upwindmost-corner to low-downwindmost-corner, but the opposite is desirable too if you have room. If you want to look at ways of doing this, I bet you could google "diagonal bracing stud walls" or something like that to see different methods. OTOH it doesn't make much difference so really anywhere you feel you have the room to screw in a long diagonal 2x4 will probably be quite sufficient
Good luck, have fun,
Pat

It's real easy to do, just stoutly screw a few 2x4s on the major diagonals of all walls. Most important are diagonals going from high-upwindmost-corner to low-downwindmost-corner, but the opposite is desirable too if you have room. If you want to look at ways of doing this, I bet you could google "diagonal bracing stud walls" or something like that to see different methods. OTOH it doesn't make much difference so really anywhere you feel you have the room to screw in a long diagonal 2x4 will probably be quite sufficient

Good luck, have fun,
Pat