Install a GT2 pulley onto each motor shaft. The set screw side of the pulley should be nearest the motor.
On each motor, tighten the set screws to lock the pulley into place. It should be at the tip of the shaft.
Using four M3x8mm machine screws, install a motor onto the left back leg motor bracket. The wires should face towards the front of the machine.
Repeat the previous step for the motor on the right back leg.
Into the left front leg, insert a GT2 idler and use an M5x35mm machine screw and M5 hex nut to secure the idler into the space for it.
Repeat the previous step for the idler on the right front leg.
Move the gantry to the middle of the frame, then insert an end of the GT2 timing belt into the belt slot nearest the front of the machine on the left side gantry. Ensure the teeth are facing towards the middle of the assembly as you insert the belt.
Take hold of the belt on the v-slot side of the gantry and work it to the end of the gantry, around the idler and along the inner side of the v-slot extrusion. Ensure that the belt passes underneath the gantry as you work the belt to the motor end of the extrusion. Pass the belt around the motor and along the outer side of the extrusion until you reach the gantry. Then pass the belt through the belt slot on the gantry.
Secure the short end of the belt to the gantry using a belt clamp and two M5x15mm machine screws. For adjustment, you may want to leave 2-3 teeth past the belt clamp.
Pull the unsecured end of the belt taught and secure with a belt clamp and two M5x15mm machine screws. Cut the belt on the outer side of the gantry such that there are a few teeth available for tension adjustment.
Repeat steps 7-10 on the right side of the gantry.