. Connect all the chain links
. Remove the hotbed, then remove the 3 screws on the lower cart. Place the hotbed support and screw it back. You need longer screws here.
. Insert wires in the hotbed mount, through the chain, connect the chain to the hotbed mount and route the wires toward the back of the printer.
. Install the frame mount removing the two screws on the frame and then putting them back. You don't need longer screws here. Pay attention to the wires under the mount, to not pinch them between the mount and the frame.
. Now reinstall the hotbed TURNING IT 90° ANTI-CLOCKWISE so to have the wires connector on the left, going exactly inside the hotbed mount. Luckily this printer has a square hotbed :) Reinstall the connector before putting it in place, and then screw it back.
. When all is in place, you need to cut the white lip on the hotbed connector, because it protrudes some mm up and it could interfere with the extruder when going home. Don't worry, the connector won't disconnect itself when inside the mount :)
. Route the wires on the left, under the frame to the main board and reconnect them.