This is the setup I use when using split dies.
About 20 years ago I spent a couple of days machining a couple of tailstock die holders and different size split die holders.
The idea is once the split die is set and cutting the correct desired size/fit, it remains in its own die stock holder until such time it becomes damaged or blunt.
If I haven’t got the correct size die set I simply grab another die stock holder and set it up. After it has been set and used it is stored in the draw for the next time it is required. The obvious advantage is once set, you know it will cut the same again and again. These can also be used in a standard hand held die stocks but the biggest advantage is the time and effort they save.
The Home Engineer