This is the new version of my wall mounting system. The upgrade is just an increase in the size of the mounting screws from M2 to M3. The old design is here: https://www.printables.com/model/540202-lego-speed-champions-vertical-wall-mount
The type of holder needed varies based on the wheelbase and the width of the car. Early sets are 6 stud wide. Sets from 2020+ are 8 studs wide. I've only included the compatibility of sets that I own. Feel free to add a comment for updates to compatibility, or to request different sizes.
The modular sections can be attached to each other with an M3 (8mm length) screw and m3 heatset insert, or with a small woodscrew (#5) into the wall. Alternatively, The sections could just be screwed together with heat sets, then attached to the wall with command strips.
Screw: https://www.mcmaster.com/91294A128/
Heat Set Insert: https://www.mcmaster.com/94180A331/
Wood Screw: https://www.mcmaster.com/90031A131/
Type A: 8 wide 11 stud wheelbase
Type A High Compatibility: 8 wide 11 stud wheelbase with additional cutouts for low ground clearance cars
Type B: 8 wide 12 Stud Wheelbase
Type C: 8 wide 15 stud wheelbase
The author marked this model as their own original creation.