This is an easy print that can be printed in few hours but supports are very important, check my images to look where I put them. If your slicer software doesn't allow you to add/remove supports manually, don't worry, it should be smart enough to do a good job ny itself.
We have a Prusa i3 Hephestos with a 0.4 nozzle. All these parts were printed with 0% infill, 3 perimeters (or 1.2mm shell if you use Cura) and a layer height of 0.3. All the parts are strong and they look very good, but if you want a better looking surface reduce the layer height.
Part 01 has four very small points touching the bed, to improve adhesion try to add three lines of brim. It makes a huge difference.