Lego piece display

Hey guys, I’m very new to 3D printing (got my first printer for my birthday a couple weeks ago) and loving it so far!! I have a wee project in mind that I’d really like some advice and tips on!!

My wife and I are avid LEGO builders and we have attempted to make a cool storage frame for all our excess pieces, we made it from a picture frame with felt glued to the back of the glass with a LEGO figure carved out, fill the frame with pieces and you can see the outline of a LEGO figure!! It didn’t work so great as you can see in the photos and so I thought, how about printing a thin rectangle with the outline in that I can put in the frame instead of the felt!!

I would need to print it in 4 quarters and glue them together du to the print bed not being big enough, so my first question is, once I have the design, how do I cut it up into 4 quarters to print?? Second question is where to start with making the actual design, I can’t find anything pre-made like this so would possibly have to start from scratch!! I’m not CAD savvy so currently just using tinkercad to mess around with and Cura as my slicer!!

TIA for any and all advice!