GTA 5 Mods Roblox Underground War Map

First, extract the zip file.
Then copy or drop the map/prop files into the addonprops folder.

Next, open the Prop Editor and rebuild it using the same mod file name.
After that, go to the Scripts folder, open objectlist, and paste the same mod file name there.

Finally, start your game, open Menyoo, and search for the object name.

Enjoy