Papilio Lite extruder HGX r3.1 with shoulder screws

The goal is to solve the overtightening situation.

The original assembly method is to manually feel the tightness by moving gears; it works fine, but I want to try other methods. The idea is to use shoulder screws to limit how deep the screw can go.

Here is the change I made:
use shoulder screws.
use M2.5 heat inserts to match shoulder screws.
more space for drive pulleys, about 0.5 mm.
more space for primary gear, about 0.5 mm.

Hardware requirments:
(Please check the pictures for actual dimensions.)
shoulder screws: M2.5*4    x4
shoulder screws: M2.5*18    x4
heat inserts: M2.5*5*4.5    x8

Build instructions:
Mostly follow the original intructions but different is heat inserts install direction, all 8 heat inserts install from bottom of upper base, and it is critical the heat inserts must aligned with bottom surface.