Developed a simple magnet mounting fixture that allows the 6mm dia x 3mm t magnets to press in. 

Arrangement of the magnet holes allow for 6 or 7 in a circular pattern (middle filled or not). Also includes a straight line for up to 5 magnets. This arrangement will allow for several different arrangements in symmetric patterns from 1 to 7. 

Magnet interface holes are designed to contact the cylindrical surface on 3 sides with small flexures built in. 

Printed 2 copies in ABS for fit check.

Magnets press in well and are retained tightly. 

Placing the fixture face-down on a flat surface you can press the fixture flush with the surface and press the magnets one-by-one with a small screwdriver or pin to align them all with the same surface on the fixture. 

Next step is to add features to connect one to the digital scale connect one to a small pull handle or fixture.