Added recesses to the original model components to allow for installation of magnets to join the components. I used 2 different sized magnets: 6mm x 2mm and 10mm x 3mm - links below.
10x3: https://a.co/d/42hyNjZ
The fit of the magnets is very snug, but a little bit of glue may be needed to keep them in place. I made multiple different signs, and this was an easy way to allow for them to be changed out.
The author remixed this model.
Added recesses to the original model components to allow for installation of magnets to join the components.