I printed the Parametric Rugged Box for another project and thought it was an awesome model that worked really well. I had a set of Parkside PSB 6 A1 stepped drill bit that I wanted to make a case for for a while and thanks to the awesome model by michael.1308 I didn't even need to measure anything.
To prevent the smaller step bits from dislodging from their place and bashing around the case I just cut some black sponge (about 15 mm tall) and glued it to the case lid. I cut mine oversized as it helps hide uneven cut lines.
I attached the fusion file in case yours doesn't fit and need to tweak things.