There is a common problem with the Two Up. Due to the design of the printer the extruder stepper exerts a large amount of leverage on the two 8mm rods. this can cause a small amount of flexing in the frame and causes the nozzle to "sway" in the y axis. This mod also lifts the entire extruder increasing the overall print volume. This also helps the printer create a better first layer as the x carriage is lower to the bed and therefore more rigid. This rotates the entire stepper and extruder 90 degrees. This is based on DDeGonge888's extruder body. This is the best extruder I have used.USE CAUTION WHEN PRINTING FAN MOUNT! PRINT FAN MOUNTING SIDE DOWN AND ENSURE THE PRINT DOESN'T WARP AS ITS PRINTING. GOOD AIRFLOW IS NEEDED! Once offset has printed cut out 2 thin wall sections to allow stepper motor shaft to pass through. Use 3 x 5mm white LEDs in series in the 3 holes. Use a 330 ohm resistor as a current limiting resistor. Hook them up to 12V. Use 6 x M3 nuts. 4x in the faceplate to allow bolting thru to X carriage. 2x pressed into 2 slots to allow fan mount to have a hard point thread.