1. Put the sage bunches in a large bowl and cover with cold water. Soak for at least 2 hours.
2. In a nonreactive dish large enough to hold the pork loin (or in a large zippered plastic bag), combine the oil, orange juice, honey, lemon and orange zests, oregano, garlic, and cracked pepper. Put the pork loin in the dish and turn to coat. Cover and refrigerate for 2 to 4 hours.
3. Prepare a charcoal or gas grill for grilling over a medium-hot fire. If using charcoal, mound the coals to one side of the grill for indirect grilling. If using a gas grill, turn one of the burners to low. Lightly oil the grill grate.
4. Lift the pork loin from the marinade, scraping any excess marinade from the meat back into the dish. Set the pork aside for 15 to 20 minutes to reach room temperature.
5. Meanwhile, spoon the marinade into a saucepan and add the bacon. Bring to a simmer over medium-high heat and cook for about 15 minutes, or until it has reduced to a sauce like consistency. Remove and discard the bacon. Transfer the sauce to a blender and blend until smooth.
6. Season the pork on all sides with salt and ground pepper. Place the pork over the hottest part of the fire and cook, turning as needed, until the pork is well marked and browned on all sides. This should take about 10 minutes.
7. Brush the pork loin on all sides with the sauce, move it to the cooler section of the grill, and cover the
grill. Let the pork loin cook for about 45 minutes to 1 hour, turning once or twice during grilling, or until an instant-read-thermometer registers 145F when inserted in the center of the loin.
8. Remove the cover from the grill and lay the squash in a single layer next to the pork loin. Lay the 6 sage bunches on top of the squash. With care, roll the pork loin over the squash so that the fat side faces down, on top of the sage and squash. Cook for 10-15 minutes or just until the squash is tender.
9. Transfer the meat to a cutting board and let it rest for 10 minutes before carving. Place the squash on a warmed platter large enough to hold the squash and the sliced pork. Slice the pork and arrange the slices on top of the squash slices.