Haven't heard of any manual tranmsissions coming what so ever in the NNBS trucks. I know the 6.2L Denali's and 6.0L 2500HD's come with the 6L80. Talk about an awesome shifting transmission!! Look to be pretty bullet proof too.
2000 Chevy Silverado RCSB LS6 5 speed, LS6 short block, 317 heads, LS6 intake, Lunati 220/224 .575/.575 112LSA cam, Edelbrock Headers, CTS-V accessory drive, Nelson Performance Custom Tune.