yes, fairly easy solve, but a peculiar reverse formula in which one goes back to identify the "manipulated" clues - without affecting the result ...
I have all but one and if it's 24, as I suspect, I can't see how it works.
I echo prospero's comment: I solved the whole thing, revealing the message in the grid, and honestly couldn't really be bothered going back and figuring out which clues the message refers to since it has no bearing on the grid.