Geeetech i3 Clone V2 - Z axis

This is a Geeetech i3 Z axis modification. Mine is the plywood version, so it may not be good for acrilic or other versions.
The final Z printing area depends on the extruder throat length, I have a 50mm throat and I reach 235mm; the original Geeetech throat is 38mm long, so the printing area will be about 245mm.
There are some parts to extend the top of the printer, without major modifications of the frame, there will be the need to drill just two 3mm holes. The other parts are the step motor