Upgrading from GTX 970 to Vega 64. Will also be updating 10.13 -> 10.14. What is the ideal way to do this?

Hello, I recently got a brand new VEGA 64 for a low price. I have a system with High Sierra using i7 4790 & GTX 970. I want to upgrade to Mojave now. I was thinking of installing the VEGA in High Sierra itself and then upgrading to Mojave using the update method. Will this work?