An alternative is to get a trencher that will make a trench 150mm wide trench the perimeter 500mm deep , form up 200mm above the trench on the back and sides , pour the cement directly into the trench and place anchor bolts in the concrete before it hardens for the floor plate , the area between the trenches is poured later as the floor slab .
The sheeting is placed on the outside then as you mentioned and kept an inch of the base to stop rusting
I did that method in Kentucky where you have to put foundation below depth where it freezes to prevent frost heave , however it is a sturdy way of construction (building survived a tornado ).
You have a sweet shed , maybe if it had screened louvers in the apex at each end of the gable it would keep it cooler when locked up and look more aesthetic ?
Yes the stud height is important too many sheds built too low
Did you have to cut the safety frame to lower the tractor canopy?
I have no racking or internal lining just use the shed's wood framing as shelving
