That looks totally awesome, brother. I love it.
To protect the GPU SMDs around the core you can use clear nail polish, the red Thermal Grizzly conformal coating (or other conformal coating) and the Thermal Grizzly GPU Guard gasket. I use clear nail polish covered by the GPU Guard, so double-protection. My recommendation would be doing that. You not only protect the SMD components, but everything else beyond them. The gasket also minimizes exposure to air, so the liquid metal should be less likely to oxidize.
https://www.titanrig.com/thermal-grizzly-tg-gpu-guard-nvidia-gpu-set.html