if you don't have brown just don't use it. its not that visible anyway. just start black then change to white on layer 15 then follow the rest

Print at 100% infill with a layer height of 0.08mm with a base layer of 0.16mm

Filaments Used:
Black Transmission Distance: 2.7
Brown Transmission Distance: 1.5
White Transmission Distance: 4
Yellow Transmission Distance: 7.1

Swap Instructions:
Start with Black
At layer #12 (1.04mm) swap to Brown
At layer #15 (1.28mm) swap to White
At layer #16 (1.36mm) swap to Yellow for the rest.