Mount the profile (Pos 8, brown colored, 305 mm)
between the two cross beams.
5.4.3 Mount the Cross Beam for BOTTOM Printer
Slide on the top profile (Pos 5) four M8 slot nuts on
each side.
Put the two cross beams (Pos 1, green colored,
2105 mm) on it. Check that the notch for the screw
head is on top. Use for each side two M8 screws to
fix the cross beam to profile Pos 5.
Mount the profile (Pos 8, brown colored, 305 mm)
between the two cross beams.