I am very new to CAD design and Free CAD. I am trying to design a platform for an aircraft part that is basically 75mm x 75 mm, but each side of the box has a different height, i.e. front left is 9.4mm, back left is 12.83mm, right front 14.4mm, etc. I can't figure out how to draw this and extrude (pad) it. It seems that I can only make the box shape with equal heights all the way around. I need to mount a device onto this bracket so that it is level in flight. Help. I am pulling my hair out.