A talented bunch of programmers over at GTAGarage and GTATools have created an incredible program, a bit like the Vice City Mod Manager, except this one is for GTA3, Vice City AND San Andreas. The current release state doesn't have a working browser, however it does let you view all the vehicle models. You can easily install any vehicle modification, and also create packaged mods for easy distribution.
The program creates CAR packages for your custom made cars complete with all data needed for installing the car and checks for the need of Dmagic1 wheel mod so that almost nothing can go wrong during installation, the program also contains many useful features which are dedicated to car modders such as manual car data installer and San Andreas col into dff merging which will be extremely helpful in the future. The program works with all 3D gta games, that are GTA3, Vice city and San andreas.
We'll be adding both the traditional install mods and CAR packaged mods for future uploads. We'll probably also add a mirror for the mod manager too.
Download GGMM - GTA Garage Mod Manager.