Use a Double-V Adapter
It is possible to use a double-V adapter to mount two dies next to each other.
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To do this manually, use the Add Adapter button to add an adapter to a die, and then use the Change Tool button to change that adapter to a double-V adapter. Now, it is possible to add a second die to the other slot of the double-V adapter using the Add command from the command-bar and choosing a die mount. When you have a die mounted one slot of a double-V holder, you can shift it to the other slot by clicking on the DV Shift button that is displayed.