Recreated the 2-tier keyboard display stand from soda22 (which is originally based on the TrashiStand) from scratch in Onshape so that I could add a lip to the second tier and adjust some dimensions. Here is the Onshape document if you wish to make adjustments/remix it for yourself.
I've included a version that is near-identical to the soda22 model but with the front lip on both tiers of the stand as well as version that is slightly taller without making the dimensions too wonky to allow for an original single board TrashiStand to be placed in front without obstructing the boards too much (see photos). Works with the original support brace files as no changes to the bracing slot were made.
The author remixed this model.
Recreated the soda22 model for 2 keyboard in Onshape to allow for adjusting dimensions and adding a lip for both tiers of the stand (as well as any future edits/adjustments)