From what we know so far, your dad & Guidry entered the 78th division line on the morning of 21 March 1945 contacting some guys in a jeep.
The Sieg River was designated by General Bradley as the northern limit of the Remagan bridgehead. On 13 March the 78th`s line had reached Honnef, about 4 miles from the Sieg. The 78th reached the Sieg River ON the 21st establishing their line from the Rhine eastward to the autobahn. The north side of the Sieg was well defended by the germans so there would have no patrols across the Sieg and the units of the 78th would not have been close to the river in sight of german artillery, but back maybe half a mile to a mile from the river.
So for them to see a jeep, they had to have crossed the Sieg.
Wherever the farmhouse was, north or south of the Sieg, the farmer knew the american armies were coming soon and figured it was in their best interest to help the escapees.
http://www.ibiblio.org/hyperwar/USA/USA-E-Last/USA-E-Last-11.html
