If you look along the Z-axis supports (the ones with the bearings), you'll probably notice that they curve due to the weight of the bed. This was a concern for me as I don't want the bed flexing as more plastic gets added to a print.
Many of the Z-support designs avavilable require that you dismantle the entire Z-axis to insert them. I designed these to just slide into place. You need 4x m5x30 nuts and bolts, and 4 m3x10 bolts.
The author marked this model as their own original creation.