George, I'm not sure what you mean by "unit service records". Your subject line is "Tank Division WWII Records". Are you seeking unit records, or his personal records?
If it is the former, do you have his unit info?
If it is the latter, have you tried to get his personnel record from NPRC? If not, info on how to do so can be found at this web page: http://www.archives.gov/st-louis/military-personnel/index.htmlhttp://www.archives.gov/st-louis/military-personnel/index.html They had a disastrous fire in 1973 which destroyed many records. However, depending on what info you are seeking, that may still be the place to start.