I don’t own a framework 16 but i heard that some people who do have trouble with the fit of the spacers. I think one way to solve this is to have a module that spans the entire width of the laptop with an offset track pad. This module would have pins appropriately placed on the top and bottom so that the track pad can be shifted to the other side of the board by simply rotating the module 180 degrees, making it viable for numpad left and numpad right configurations.
However if we naively do this the mouse movements will be completely flipped when the trackpad is upside down. We could perhaps solve this via software on the computer. I think a better solution would be to have some processor on the trackpad module flip the trackpad signals when it is upside down so the pin output leads to the right mouse movements without having to implement new software on the computer itself.
To avoid redundancy and reduce cost the module could be sold without the trackpad. The user would remove the trackpad from their existing module to use it on the full width offset trackpad module.