Install Realism Overhaul with all its dependencies for KSP 1.8.1.
Install Real Solar System.
Install RP-0.
Place the modded Real Solar System folder in the GameData folder and replace all.
Go to RP-0 folder, delete the contracts folder and replace with the modded one.
Open the game and create a new carrer on Mars. Enjoy :)

For updates of the mod, just replace the Real Solar System files with the new ones, delete the contracts folder in RP-0 and replace with the new one. (you need to delete the old one to avoid duplicate contracts)
For comms to work on new launch sites added, you need to delete the "RemoteTech_Settings" file in your save files so the new comms apear on those launch sites when you load up your save again.

This is a project i'm doing just for fun, there's probably some things wrong, just so you know.