Speedo cable for automatic

Hi folks, looking for advice from anyone with an automatic. The car is a 1.8 carburettor engine with auto box 1989. Looking for a new Speedo cable, part 172957803N which are like hens teeth. I can get a Mk2 cable, part 192957803c which looks the same but is 400mm longer. Has anyone fitted this cable? Was it the Same, just longer? Any issues?
Cheers Steve.

Edit. If anyone can move  this to the Help section or tell me how, that would be appreciated.