I've included a properly setup 3mf file with tree supports for the connectors. Each uses about 20g of filament and takes ~45 minutes (on Bambu X1C).
I've also included a STEP file and STLs. Enjoy.
The author remixed this model.
UPDATED Jan 30, 2025:
After using these for many months, I realized the push-fit and snap connectors weren't optimal. Moved to the pegboard click connections and I like them much better. I also setup the 12V ones to support the bigger 12V batteries by setting the holder sufficiently far from the multiboard to work with the larger 6Ah form factor.
ORIGINAL:
Added options for connecting to a multiboard:
Snap connectors are rotated 45 degrees to remove some support needs (and they can probably be printed without supports). Removed the screw holes from the original. I first made it a STEP file via Fusion360. The model was further modified and mated with multiboard's remix connectors in Shapr3D.