I asked Nathan to measure his 5th gen trim. Thanks again for that, and here are the results
"The 5th gen is 78cm at the sides (if you square off the corners). They also disappear under the scuttle panel, so they are longer than that really. Then it's 112cm across the top.
The 4th gen is 79-80cm at the sides (to the ends) and 112cm across the top.
So it looks like they'd fit, but I obviously don't know about the clip/profile."
So I am ordering one
Even if there's a small difference somewhere, 5th gen trim is soft rubber one, so it should adapt.
Yellow Dream made true.