I highly recommend slicing with Arachne and using a single perimeter on the first layer. Also, make sure to load your white and orange filaments before the black, as PrusaSlicer starts the print in the order the toolheads/filaments are loaded. If black is loaded first, you risk contaminating the areas meant for white and orange.

I designed this with the print bed size of the MK3, MK4, and Core One in mind, but I didn’t account for the space needed for the purge tower. It might still work—perhaps try resizing it in the X and Y axes? Leave a comment if you give it a go!

I printed mine in PETG using a 0.4mm nozzle and a 0.2mm layer height.