Make any GTA V car bulletproof, window by window, like the armoured Kuruma, and give it tyres that never burst. Right in your browser: no ZModeler, no Blender, no CodeWalker.
Pick a game car (or drop your add-on's .yft, _hi.yft and .ytd), untick any window you want to leave normal, tick the tyres, and download the FiveM resource: the game car replaced, or a new add-on car. In this video I armour the Buffalo, fill it with NPCs and try to shoot them.