ELS installation is very simple. After downloading ELS, put the "INSTALLATION FILES/Grand Theft Auto V" files in ELS in the main directory of the game.
First you need to download the original model and install "policeb.yft", "policeb_hi.yft" and "policeb.ytd" files. After installing, you need to download the file I uploaded here and replace the "policeb.ytd" file with the original one. You put the "POLICEB.XML" file in the 'GTA 5 folder > ELS > pack_default' directory.
Note: My car models are located in 'GTA V/mods/update/x64/dlcpacks/patchday22ng/dlc.rpf/x64/levels/gta5/vehicles.rpf'. The models I upload here change automatically in the game. My motorcycle model is also here.