i have designed a PTFE Cutting Chamfer Tool for the MMU2 since there is nothing arround. This is for the 5 PTFE tube with length of 19 mm. Additional they need a phase from one side so you'll need to chamfer them.
you have to push your PTFE tube into the printed form until it stucks, then cut it with a cutter knife, when you have finished this with all 5 tube take a chamfer preferable as shown in the picture, put into you drill and chamfer it. When you have finished it open the form take out the tube and there are ready to be installed in the mmu2