✅ How do I pin both NET 8 and NET 6 sdk versions in global.json?

hi everyone! if I pin the 8.0.204 sdk in global.json for some reason it wants to pull version 6.0.35 of the Microsoft.NETCore.App.Ref nuget package. is there a way to pin both the 8.0.x and 6.0.x versions of those nuget packages? at my company we are using internal nuget repositories and we don't have a way to pull those internal SDK nuget packages automatically