Accidently the part 104 was missing for my LC+ printrbot. So I designed a new one. In that case, I redesigned it so the stepper motor fits better and the z-end switch is more centered. Part 104 is now 5mm thick h104b).
Instead of zip tying better use M2 screws to fix the part with M2 washers and M2 bolts as shown in the picture. My M2 were a little bit too large, instead of 28mm you can use shorter ones.
I provided also the 6mm original thickness as stl file (h104), in case you have different tolerances. For any inbetween you can add washers. Its very tricky to get the switch at the rioght position, so its not colliding whith the hole when activated.