Sorry for the late response. You would have to find it in the armor section. I cant give you an exact number since it really depends on where you placed the vest itself in your files.
you probably replaced the wrong ytd file. the name of the file is named after the folder that the modified badge and nameplate folder it is supposed to go in.
Because with EUP 8.2, you cant put the proper badge on the hat without there being a 3d model of the 5 point badge that's originally on it. Meaning i could do the hat but it wont look good at all. And as for the high vis vest.. ill get to it soon.
With these pants the YDD for the pants aren't in EUP. The folder that the pants are in the pack is the name of the folder the textures go into in EUP. so it would be mp_m_freemode_01_mp_m_gunrunning_01.