Install the navy revolver mod as usual whit the mod manager or directly to the lml folder.

Example:
X:\Program Files (x86)\Steam\steamapps\common\Red Dead Redemption 2\lml\navy_revolver_sp

If the NAVY Revolver mod stops working, change ScriptHookRDR2.dll to a newer version. Right now, the ScriptHookRDR2.dll that I provide in this file is the last one that works. Never change ScriptHookRDR2.dll, dinput8.dll or version.dll that I provide in this file and copy and paste them into the main folder of the game unless it stops working just changing ScriptHookRDR2.dll for a new version. Finally, if you replace ScriptHookRDR2.dll and the other files provided, before starting the game, go to the root folder and delete the files asiloader.txt, ModManager.txt, ScriptHookConfig, ScriptHookRDR2.txt and vfs.txt. 

Now, enter the game, use Rampage, go to the navy revolver selection menu in multiplayer weapons and select the revolver. If you can select the revolver and have used it in a previous save, simply reload the save and voilà, you'll have your revolver again.

Drag and Drop the files provide to the game root folder

Example of the Root Folder:

X:\Program Files (x86)\Steam\steamapps\common\Red Dead Redemption 2

ScriptHookRDR2.dll
dinput8.dll
version.dll
