From the link that Kurt referenced in his previous post are the following excerpts:
Battery Usage
"67, 68, and early (pre-May) 69 L6, 307, and Z28: The standard battery was the Delco Y55."
"67, 68, and early (pre-May) 69 327, 350, 396, and 427: The standard battery was the R59."
My question is, did the 327/210 Hp variant get the R59 battery or was R59 usage limited to the L30 327/275 Hp engine? I would have thought that the 327/210 Hp engine and the 307/200 Hp engine would have used the same battery.