I printed the parts but the z nut plate (the part that is fixed at the frame) is too thick (6.6mm). The original has ~4.4mm.
When you insert the screws, there is only a few mm left to insert the t-nuts, the screw is only 10mm long. The t-nuts don't turn to thelock position inside the metal structure because of it.
Besides that, the holes to insert the screws are too tight...
The rest is perfect. I'll adjust the mentioned part and print it again to test it.