Waterproof Case for ESC

have several EMAX SimonSeries 12A ESC's that I want to use in a small RC watercraft and was interested in any "how-to's" about waterproofing the ESC ... as it appears that the ESC is the component of an airborne (or waterborne) that is the most susceptible to water damage ... most solutions involve imbedding the ESC in heatshrink or a conformal coating, however, these techniques offer no method for heat dissipation ... so it was neccesary to develope one

I already had the ESC's ... then found 22mm x22mm x10mm anodized aluminum heatshinks on Amazon (Gadgeteer 10pcs Aluminum Heatsink, $8.99 for 10) ... the 3D printed parts were printed in PETG on a Makerbot 2X ... the factory heatshrink was removed from the ESC and the aluminum heatsink was attached to the surfaces of the I.C.'s utilizing the double-sided thermal transfer tape that came with the heatsinks ... the heatsink/ESC assembly was fitted into the 3D printed case with the heatsink fins protruding through the hole ... the gap ar