As my P1P sits in an enclosure and it's difficult to reach behind it, I cut Enrico Pulvirenti's excellent poop chute in half and added magnets to both hold the parts together and to hold it to the back of the printer. You will need 24 8x3mm magnets to do this build. I also shortened the side chute a bit to help it fit on the plate. You can print both parts at one time if you want, without support.
(PROTIP: mark one side of your magnets with a Sharpie as you pull them apart to help you keep up with orientation; this is a lot of magnets to keep up with.)