
The pork roasts at 375°F; the potatoes want 425°F. Easiest move: slide the potatoes into a second oven or pop them in after the pork comes out to rest. They can hold loosely tented with foil while the pork finishes. Either way, start checking them around 45 minutes.
If the pork starts browning too quickly before it's tender, tent loosely with foil for the last 30 minutes.
Don't skip the basting — the orange juice reduces down to a sticky-sweet glaze in the bottom of the pan. Spoon it generously over the finished pork.