STORY
Sneak inside the Humane Labs Research Facility, find the scientist, and kill him. The mission will be stealth in the beginning, but will go combat once you killed the scientist.

GAMEPLAY
Mostly played in a interior
Enemy Reinforcements
No Police
No Gangs
Stealth & Loud

Installation:
1. Install Scripthook V and ScripthookDotNet

2. Install Mission Maker
https://www.gta5-hub.com/scripts/mission-maker

3. Put the mission files to Grand Theft Auto V\scripts\MissionMaker\missions

4. (Optional) A trainer, to put a silencer into your weapon

If everything is correct, you should be able to play the mission.
Also the mission comes with a Tutorial Mission that takes place inside Mission Row PD, which you have to escape from to complete. It has some basic stealth gameplay.