* Balance: The 360 is externally balanced, meaning the crankshaft's counterweights are external to the crankshaft itself. The 727 was designed to work with this external balance. The 46RE, however, is internally balanced (or designed to work with an internally balanced engine). Using an externally balanced engine with a 46RE will cause severe vibration and potential damage.
* Input Shaft: The input shaft of the 727 is not compatible with the 46RE's flexplate and crankshaft. They use completely different splines and diameters.
* Torque Converter: The torque converter for a 727 will not fit a 46RE.
* Electronic Controls: The 46RE requires electronic control modules and sensors that the 727 lacks. You'd need a complete electronic control system to make it even remotely functional.
To use a 727 behind your 360, you would need the appropriate flexplate for an externally balanced 360 and a 727 torque converter designed for that engine.
In short, this is a major incompatibility and requires a complete transmission swap and potentially other drivetrain modifications. It's not a simple bolt-on replacement.
