Hi,
To my knowledge, they are confusing the W113s with W108/W109/W111 cars. Only the W108, W109 and W111 cars got the new version Aut. transmission with a torque converter when it became available around spring 1969. The 280 SL and 109 6,3 where produced until production end with the GA type transmission
and the Fluid Coupling and not a TC.
Hans