How to Install a 4L80E into 1967 - 72 C10 / C20

[Accelo]

The only reason this transmission is not used more is the cost of the controller as only fully electronic versions were manufactured. The stand alone controller can cost close to a grand. If you are transplanting an LS motor using a computer it can be used to run the transmission for a lot less money. It's covered in the video but without cost information.
The speedometer is also electronic and requires some type of conversion to work with the stock speedometer. It will connect to the aftermarket speedometers directly.