Hey Justin, thank you for your quick response and the great guide! Plan to do the same with the knowledge from you!
Hi, I’m looking to buy a late 2015 model and I had the same idea you did. After switching the HDD with a SSD drive I would like to use the Fusion Drive’s PCIe (128 GB) for Windows. However, I read that the iMac will always install macOS on the small SSD blade. Is this true? What did you end up doing?