I am about to reinstall a freshly rebuilt engine into a W116 350SE, and in discussion with the owner, we agreed that it would make sense to provide the transmission with a new filter. Due diligence also dictated that I wanted to replace the radial torque converter seal, and front pump seal (since these always end up leaking, and require transmission removal to address).
I removed the bellhousing in order to extract the primary oil pump from behind, and replace the seals. All went well...