I designed these weapons closely based on some very cool illustrators that Alec and his team did with their Kickstarter - Turbo Rally. They had the cards for the game but not the 3D weapons to complete the game cars, so I offered to help them out with these being the result which are scaled (1/64th) to suit a Jada Car and other brands similar like M2 Machines etc.
NOTE: THESE ARE APPROXIMATELY 25% SMALLER THAN THE JADA VERSIONS IN MY SHAPEWAYS STORE.
see the project here:
and another game tht has weapons on cars, here:
To fit simply, remove the joiner branch at the diameter change. You can either drill a small hole in the roof or bonnet to suit the diameter of the post on the weapon OR trim the post fully and glue the weapon to the roof or bonnet of the car. Before fastening you can paint up the parts to make them look a little more realistic if you wish so select a colour to print that best suits your ideas.
Search "swinksdiorama" for other and linked hotwheels parts.