I traveled part of SD 44 yesterday, south of the Badlands National Park boundary. I turned north on SD 377, to get back to I-90 via SD 240.
TM has SD 377's south end at SD 44 (fine), and its north end at SD 240. However, GMSV shows
an End SD 377 sign at the southern park boundary. Some
much older GMSV imagery has SD 377 signage within the park, at the junction with SD 240.