The Microfit Microjig for getting great Dado's. You will need 2 - 3 or 4 mm bolts depending on what you have there are both in the model. You will also need two inserts for the top nuts.

The other half to this model is at https://www.printables.com/model/385253-matchfit-setup-gauge.

You will have to position the model to print with few supports or to what you think is acceptable. Import into Slicer and split to objects if downloading the whole unit.