Pentode Peak is located on Inland Empire Paper ground, a permit is required.  Here is a link to the website lots of info http://iepco.com/forestry/rec-use/ .  I accessed the trailhead from the town of  Blanchard Id off of State highway 41 turn onto the Blanchard cutoff road and then head west in about 10 miles you come to the trail head from there follow the GPS tract.  It’s about 1.8 miles to the top.