Wash the potatoes and rub the skins liberally with vegetable oil. Put the potatoes on a baking sheet and bake until fork-tender, 45 minutes to 1 hour.
Slice the baked potatoes in half lengthwise, then scrape out the inner flesh with a cookie scoop or spoon, leaving a small margin of potato in the skins. Brush both sides of the potato skins with vegetable oil. Salt both sides liberally. Place the skins cut-side down on the baking sheet and return to the oven. Bake for 7 minutes, then flip the skins to the other side. Bake until the skins are crispy, about 7 minutes more.
Meanwhile, fry the bacon in a skillet until crisp, then remove to a paper towel-lined plate to cool.
When ready to serve, chop the bacon into bits and transfer to a small bowl. Put the cheese, ham, salsa, sour cream, ranch and chives in separate bowls. Lay out the fixings, put the skins on a platter and have everyone help themselves at the skins bar.