Replace nut with different string gague?

[Eviljohn½]

Hi all. Hope you are very well indeed. 

I have an Aria gt series 5 string. I put labella ltf's on when i got it. Very happy with the strings but i don't really use the low B. I'm looking to move each string over, get hold of a .030 or .035 rotosound and use that as a high C or B. For reference, i tune all my bass's and guitars to D standard, hence looking at the .035 gague for the higher string.

If i do the swap will i need to replace the nut with narrower slots to accomodate the strings as the current nut fits the strings as they are? 

Thanks for stopping by and any guidance you are able to give.