Those cowlings were put on in the first place in order to keep a stream of clean air across the windscreen when the power car is at the rear because exhaust was heavily coating the fronts of them.
In which case they may be superfluous once repainted as the EC livery is black where that would be an issue.
43239 and 43305 are in National Exppress livery and have had it removed by the looks of things.
Those cowlings were put on in the first place in order to keep a stream of clean air across the windscreen when the power car is at the rear because exhaust was heavily coating the fronts of them.
MTU's have been known to run hot, which can make the exhaust deflector crack around outlets... As a result the deflector peels back, and can then touch the OHLE...