This is actually way more simple than you'd think, not as simple as mounting games currently is but still simple.

You will either need the program Notepad++ or to open the file using normal notepad already on Windows (For any other OS, I don't know, sorry.)

You'll want to open (Or create if this file doesnt exist already) the file named "mount.cfg" in your garrysmod/garrysmod/cfg/ folder,

If you already have the file just add the one line you see here titled "bms"
If you're creating the file paste this and save it into it:
- Note if your steam is installed somewhere other than "Program Files(x86)" you will have to fix that yourself.

Quite literally put, that's all you need to do. The Black Mesa content is now mounted, Launch Garry's Mod and go to the "browse" section, and check under "all" to find the Black Mesa folders.



I want to make some last minute notes here:
- Some models making spawn icons WILL crash your game like that of some Portal 2 or L4D2 models do.
- Some ragdolls do not spawn properly, and will have disfigured bones.
- Some materials are over-written with those from other games.