'Waterproof' cap for 1T4 electric bike wiring harness

On my custom built electric bike, which uses a 1T4 waterproof wiring harness/plugs, I did not use the electric cutoff brakes because my brakes are built into the shifter. As a result, I had two unused plugs hanging off the front of the bike, exposed to weather and dirt/sand. I wanted to cover it, so I made this model.
Hopefully it fits snug enough to be waterproof on its own, but to be safe, I filled my connectors with dielectric grease before installing the cap. I did the same with all other connectors, used or unused, on the bike and I would recommend that too.