Further digging reveals that stones 57 and 58 fell in 1797, and they do not seem to be upright in the woodcut as they would obscure the view of the lintel and upright, making the woodcut post-1797. Not 1979 as I keep typing!

In Chippendale's Stonehenge Complete the 1716 painting on p46 shows a slim fallen stone in roughly the right area for the woodcut, and again on p107 there is a fallen stone under the leaning sarsen of the outer ring that seems very close. And also in the photo on p135 there is the stump and stone of 36 and 37 in roughly the right place too.

Enough!

Still, better than watching England play Rugby...