I'm not really sure on the Rice Brothers, only on the research that has all ready been done on the 2-6-0's. You're right, though, on the Northern Division there were a lot of oil conversions.
The amazing thing to see in looking at the photos is how easily the C&S shops seemed to be able to convert a locomotive. When 900 is photographed on the South end, it's coal, on the North end, oil. Sometimes within a few months of each other. The C&S shopmen were obviously no slouches when it came to practicing their crafts.
Rick