Widening loading gauges on branch lines

[GlitterUnicorn]

Are there any cases where isolated branch lines have/could be very easily modified to have an increased/European standard loading guage? I understand this would be impractical for the entire network but eg. on the Far North line where there are no tunnels and comparatively few structures it might be possible to make these changes without too much difficulty.

There could be some benefits in terms of freight and maybe using better rollingstock (replacing a 158 with an ex-Danish IC3 would be a nice improvement), or as some kind of trial for converting more of the UK network? Mostly this is just idle curiosity though.

Has this ever been done? Are there any major blockers I'm not aware of?

 

[Dave_Cardboard]

Could there be a few issues getting the required rolling stock to any such isolated branch lines....? Both for initial delivery and/or maintenance and servicing. Unless they are going to go by road!

 

[GlitterUnicorn]

Could there be a few issues getting the required rolling stock to any such isolated branch lines....? Both for initial delivery and/or maintenance and servicing. Unless they are going to go by road!

I imagine it'd have to come by road or sea initially? Would imagine that's not the largest problem though.