GF Class 108 DMU roof head code boxes

[gary littlewood]

The GF class 108 DMU has the destination box on the roof.
The 108 I remember has a 4 digit head code box on the roof and the destination in the middle window.
Does anyone know where I can get a conversion kit so my 108 has the 4 digit head code box on the roof please?
Thanks Gary

[Newportnobby]

Looking at the Bachmann spares site shows only bodies with destination boards at the roof

https://bachmann-spares.co.uk/category/5-graham-farish-diesel-loco-spares/class-108-dmu/body-parts