AMP: 43 Location: US-87 and S-387, Chouteau Cty Reassurance shield after the 387 junction. AMP: 40 Location: US-87 and MT-80, Chouteau Cty A couple miles later, we’ll approach Montana 80 and Secondary 223. AMP: 40 Location: US-87 and MT-80, Chouteau Cty Follow Montana 80 into Fort Benton. Take 223 north towards Chester and the Tiber Dam. AMP: 40 Location: … Continue reading U.S. Route 87, S-387 to MT-80/S-223