Cache is NOT at posted coordinates. I strongly suggest that you park at shown parking for the rail trail and walk to posted coords and final. Walk will be about 1.5 miles altogether. Due to the busy road crossing, I would not take children.
At posted coordinates, you will find a witness post for a benchmark - JV3920. Be sure to log the benchmark.
When you visit the benchmark, you will notice that the witness post isn't right beside the plastic tube protecting the benchmark. Bring something that can measure inches with you. Let I be the 2-digit number of inches from the closest edge of the plastic tube to the bottom of the post of the witness post. Use 42 plus I to be the last two digits of the longitude coordinates of the final which are:
N 39 54.492 W 76 19.5xx (check in hint)
When you reach the area of the final, do not climb. You will need to step up a bit but not climb. Hiding place is within 15 feet of edge of trail. In winter I wasn't concerned about lurking critters, but in warmer weather, watch where you put your hands. Container is a camo'ed spice bottle. Please be stealthy if there are other people on trail.
Congratulations to NoBlueCircles on the leisurely FTF.