Little late, but all you need to do is subscribe to the mod. If you want to check to see if your mod's assets are present, you can take steps to check. Check out an excerpt from this modding guide: https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=488641307

Game files
Navigate to the game's install folder (/\Steam\SteamApps\common\) and take a look at the subfolders contained within. One of these folders is called override and is arguably the most important folder for any aspiring modder. Any modified game asset placed in this folder will take precedence over the original and will be able to appear in the game. A simple reskin or a modified model, for example, can easily be placed in this folder and viewed in the game.

With TSLRCM specifically, once you apply the mod the title screen will change to reflect the "restored content" version under the title, and your saves will have "modded" next to them. Hope this helps.