Good question Krusty -
As the L III's wings folded in a "Z" shape it wouldn't apply to them, although a lot of them seem to be clipped.
Wings folded - Just inboard of the 20mm cannon, and at the wingtip attachment point, i.e. where they would typically change the tip types on Spits.
Very small amount of early III's (hybrid IIc) had fixed wings.
IIc's - Clipping evidence on the Merlin 32 ones, none yet for Merlin 46 ones.
So I guess I don't know, maybe as was common in the RAF the FAA units did it on a case by case basis.
Best guess judging by pics -
F IIc's with Merlin 46 (3 blade prop, 3 exhaust stacks), yet to see one clipped.
L IIc's with Merlin 32, (4 blade prop, 6 exhaust stacks) plenty of pics of clipped ones.
L III's, plenty of pics of clipped ones.
Common link - L IIc and L III had the low alt version of the Merlin. Although as with Spits it's noway a hard and fast rule.
Seafire L III with wing folded -
