The marker is placed at 40.5948442, -78.3401015. Here’s a Google link to those coordinates.
Driving through the Main Street in Bellwood, PA, after you pass the Hometown Market turn right onto Kerbaugh Rd and go through the single lane tunnel. The parking lot will be shortly after on the left next to a garage.
Here’s a webpage from Antis Township for the Becker Road Trailhead.