* Bellhousing: You'll need the correct bellhousing for the specific engine. A small-block bellhousing will not fit a big-block, and vice-versa. These are not interchangeable.
* Flexplate/Flywheel: Similarly, you need the correct flexplate (automatic transmission) or flywheel (manual transmission) for your engine. Small-block and big-block parts are different.
* Possibly the Output Shaft: While the 727 itself is largely the same, there *might* be differences in the output shaft length depending on the year and application. This is less likely to be a problem, but it's something to verify to ensure proper fitment to your driveshaft.
In short: The transmission itself is compatible, but you MUST use the correct bellhousing, flexplate/flywheel, and potentially the output shaft, dependent on your engine. Getting the wrong parts will prevent installation.
