I have made a mod containing all the skins and three mystery machines.
I have made cheats for them.
you need cleo for gta sa from cleo.li
you will need a skin selector for gta sa.
Download it from gta inside because they have automatic installers virus free.
cheats:
car cheat
first mystery machine mystery
second mystery machine newmystery
latest mystery machine latemystery
you can call scooby by typing dog once in the game.