HappyHunter wrote:
Anyway, while thinking it through, I wonder what's the best way to
attach the 2 end studs to the wall. So, the 2 end studs will be attached
to stone walls (a mix of sandstone and some brick where it's been
repaired in the past).

I was thinking, of screws, but that could be a bit fiddly since I'd need
to drill a hole in the stone wall then line it up with the wood.

That's how I'd be doing it. You drill the holes through the studs
first, then hold the stud in place while you poke something narrow and
sharp down the holes to mark the position of the holes in the wall, then
drill those. So no problem lining up the holes.

I've been known to use my narrowest narrow masonry bit (ie on my drill)
to mark up the hole positions if it's otherwise hard to see the marks
made on the wall.

(I take it the shed is fully dry etc and there's no worries about the
timber studs/floorplate getting damp?)

David