I have answered (to some degree) my own question. I googled US Army Memorial Service and evidently discovered a list of ships that were used - SS Joseph V. Connally, hull 3143 was one of them and the only ship I could independently verify as being used to return war dead. Since she was the very first ship used there is a good amount of info available. As a matter of fact, I discovered a picture of her dockside in Antwerp, Belgium 1947 loading remains and she appeared to be painted WHITE not black. Shoots that argument. The other liberties - Mary Kimbro, Barney Kirschbaum, Robert F Burns, and the John L McCarley I was unable to verify as being used although they were listed. I used Jaffe's Liberty Ships as a basic reference. Connally is mentioned but the others are not as being used as funeral ships.
If you google SS Joseph V Connally you can find much information about that first voyage in Oct 1947. BTW, she was lost due to fire on a return voyage from NY to Antwerp in 1948 carrying a load of 4,500 coffins for further repatriation.