Hoping to start a discussion on the swap from a 6 speed to the 8 speed. Its a newer transmission i know so information is scarce but has anyone gotten their hands on an 8 speed that could explain to me what it would take?

I have a 2011 silverado. My grandfather recently bought a newer ltz with the 8 speed and i LOVE the gear ratios. despite having a 5.3 that first gear feels nicer than my 6.2 with 3.73s. I know he had the option to get the 6l80e which makes me think the CAN connections are the same. I know the 6l80es TCM is in the valve body but dont know how the 8l90e is controlled.

any info would be great help, if its not realistic i'm probably looking at a circle D rebuild with a higher stall in the near future.

-thanks