Mid Swap- w123 240d motor into w110 200

[Schmanman]

I pulled a w110 fintail from a barn in wonderful condition, and have been acquiring parts since. The motor to e be installed is a om616 from a 240d automatic, and it's going into a 1966 w110 200 with the m121 motor. The thermostat housing, the aluminum housing the water pump attaches to, and motor mounts from the m121 are all bolt on as the om616 and m121 Are nearly identical externally. I am remotely mounting the oil filter unit off the rear of the block once I fabricate the plates (unless I can buy them).

My question pertains to attaching the 240d motor to the 4spd auto column shift in the fintail. I know the trans bell housing will bolt to the 616, but the protruding center of the torque converter on the fintail trans is larger in diameter than the one from the 240d. This means I won't be able to mate the two. I am considering removing both flywheels, having them balanced to match, and using the flywheel off of the m121 on the Om616. This would allow the torque converter and flywheel/flexplate to mate if I am correct.

Any input is greatly appreciated. I know this build might not appeal to all, but I put 4000-5000 mile a year on my current w123 and plan to do the same with the w110. This swap will help greatly!

Thank you,
-Alexander