- Download Refueled modification
- Unpack it to the game folder
- Run JSGME.exe and activate the mods you like
- In-game press "T". Here you can find HIDE HUD option
The mud, dirt & water effects that splatter your screen / view are supposed to enhance the "reality" of the situation. However, what they usually do is just block and blur up the view. Read here how to disable them to get a clean view.