Responding to the OP, LT....
I am curious to know whether you ever went through with the project of converting your Suburban to a manual transmission. I own an '08 Suburban whose 4L65-HD transmission was recently TOASTED because the cooler lines blew in the radiator. YES - on some models, tranny fluid is piped to the radiator for cooling, and there is a risk that if the lines blow, coolant pollutes the transmission and vice versa, which happened to me.
So...I put up my Suburban for sale, but nobody is biting, even though it had also been upgraded to the L92 6.2L engine. Since the truck is paid for, I am strongly considering taking it off the market and doing an NV4500 project. Nobody seems to want to touch this for Suburbans, but I'm a renegade who just might try this crazy venture. I had an NV4500 in my previous truck, an '03 Silverado 2500HD, and I loved it. I only sold it because my wife was preg at the time.
So, LT...did you do it? If yes, how did it go?