The Scalplock Lookout Trail is 4.7 miles and 3,100 vertical feet on a very nice trail that begins at the Walton Ranger Station near Essex, MT.  This is a less visited side of the Park.  No entrance fees are required and it is much less crowded than many other park trails.  The following link offers an excellent trail description:

http://enjoyyourparks.com/glacierparkscalplocklookout.html

We setup in the brush beneath the west side of the summit so that we would not disturb the lookout or any other hikers that may occasion to be there.