Changing horn on T-Series

Since update 0.33 (I believe?), the horn on the T-series has changed from horn 5 to horn 121. How can I change it back to horn 5 (old horn)? I have notepad++ and VS studio code.

 

Hi! I took a look into it and encountered:
Since you can no longer select it in the parts menu, you really would have to modify the game files . This would damage the file integrity, but if that doesn't matter, the internal settings for the vanilla T-series horn sound can be found here:

{game_installation_folder}/content/vehicles/us_semi.zip
Files:
"us_semi_cabover_horns.jbeam", lines 15 and 119
"us_semi_conventional_horns.jbeam", lines 15 and 134

The sound numbers probably no longer correspond to those from the usual selection menu, as you say it is now horn sound no. 121, idk. A much nicer solution would be to actually have a different horn as a mod, where you can freely choose the sound again!
Hope that helps for now