Well, that puts close to the speculation - and exasperation - as to just where in Cove Fort, or Scipio, a SpC could be placed. So it seems that if you're headed N or S on I-15, you'll get off and loop through the I-70 & Rte 50 detour instead. That's an increase of about 14 miles (about 81 miles vs about 57 miles) - not bad, and it's also a very nice 122 miles to the Green River SpC, and 167 miles to the St. George SpC.
Nice!