These hold the latches which hold the accessories box in place when everything is stowed. The underside of the accessories box has enough space to accommodate the feet of the ground board and the two rocker bearings. The biggest mistake I made here was making the accessories box too shallow to hold eyepieces. Mirror box goes into rocker box. Upper tube assembly goes into the mirror box.
Side bearings sit on top of the ground board.
Baltic Birch plywood would have been a better choice, as ordinary plywood tends to have occasional voids and defects in it which can be annoying. All plywood raw edges are finished with birch veneer which is made by slicing thin strips off of a solid birch board. This is pretty easy if you have a table saw, and well worth it in the final result. All screw holes are plugged with birch plugs. This greatly improves the final result, but makes it so you can never take it apart again.