55mm
Infill: 5%
Top: 5 layers
Colours: 3

There are 2 different models of "Red walls" you can choose depending on the keyring you have:
6mm and 22mm models

pd: while slicing the white piece, if you want, you can adjust the position to 60° to align itself to the red walls

pd2: also, you should adjust the scale of the redwalls to 1016.5% to make them fit, sorry