Park at the Marple Mountain Sno Park overflow area which is on the south side of SR83. Plenty of parking room in the non-snow months.
Follow FR8312 to the summit which is about 4 mi one way. Easy hike up an old logging road. The summit is a site of an old firetower but is now used as a USGS Mt St Helens monitoring site. Enough room at the summit for an EFHW. Good vistas of Mt Adams but St Helens is obscured by the forrested summit.