Hey Enco59, your right, I remember seeing Hancock stations in the Houston area when I was kid. Accordind to the "Oil Company Signs" book. Signal bought out Hancock in 1958 and shortly afterwards they also bought a small chain here in the Houston area called Watson Oil Co. They then rebranded the Watson Stations as Hancock.
The only thing I know about Kayo is they were acquired at some point by Conoco. Ritters, as I understand it was headquartered in Austin
By the way, my dad always stopped in Wharton to by gas also, when were down that way. It was one of the few places in Texas that had an Amoco station, and that's who he worked for. They had a station on 59 between the Larry's Mexican resturant (if you remember that place) and the Bridge over the Colorado River.
