Vertex K8400 Pulley and Belt Replacement

After having troubles with Vertex K8400 printer's original T2.5/T19 pulleys (see my post http://www.thingiverse.com/thing:1687458), I decided to replace them with more commonly used GT20 pulleys and GT2 belts.
To perform this modification you will need the following parts:

- Two GT2 6mm wide belt rings with length 180mm (90 teeth)
- About 3.5 meters of GT2 6mm timing belt
- Ten GT20 pulleys with 8mm bore
- Two GT20 pulleys with 5mm bore (for motors)
- Four spring belt tensioners
- One