4L80e Tranny swap in an 03 H2

[Hellz]

so, i have been noticing my tranny has been starting to slip a little recently, as well as some minor power loss at HW speed (70mph) when i stomp the gas to pass someone, i will get about 1/2 a sec of power loss.

so, im looking at preparing for the tranny to give out, and what the best options would be.

right now, the 4L65e tranny i dont think is a smart choice for our H2.
even if it is rebuilt to handle more HP, the cost of the rebuild would still rival the cost of just replacing it with a 4L80e. then you have the fact that the 4L65e is only a 4 spd and the 4L80e is a 6 spd... so the MPG should/will increase with the 6 spd.

so has anyone done this swap to the 6.0L engine in the H2?
what modifications were done to make it fit.. or was it a direct bolt?

how much did this project cost?
any computer/electrical issues?

thanks