Just like the title says...I am doing a build on my OBS 97 Z71, and I have thought about going to a manual trans and keeping the 4WD for some time. At first I had notions of using the 96 and up NV4500 5 spd. However since the engine I am using is a 2005 5.3, I thought that using a 6 spd that is in the newer 3/4 and 1 ton trucks might be a good idea instead. I found info on this trans here: http://www.autoworld.com/news/gmc/zf_s6_650.htm
Also in here it says that it is mated to the 8.1 and the D-max engines. This leads me to believe that he bolt pattern for the bell housings will be different than say the 5.3, or the 6.0, but I am not sure. Is there anybody that knows if this is indeed the case? Also if it will bolt to the engine, what are the chances that it would accept the NP 241 Transfer that I am running?

Here is a pic/cut away of the trans I am referring to:

 

there is/was a member here with an avalanche that swapped one in. I remember reading the thread but don't remember if its the same bolt pattern. I do know he had to have a 3 inch body lift to make it clear the cab.

 

I just found his thread a couple of hours ago, and I shot him a PM after reading the info there. It did answer a lot, but there are still some questions I have. Some are because of all the pics are gone. The biggest being I know now from that thread is the transfer input shaft, or the transfer swap that is needed.

 

that's a freaking big transmission (over 200lbs). it'll bolt up to your motor, but, like mentioned earlier, you'll have to have a body lift just to clear the floor. it'd be a bit easier swap for you to get the NV4500. as for the t-case, i don't think the 241 case will mate up, but i could be wrong

 

Right, that is not that big of an issue as far as the size and weight go, the engine is running a MP122HH Radix. I do know that the transfer will either have to be swapped for the NP 261 or NP263, or i will be forced to swap input shafts to accept the 29 spline. The NV 4500 crossed my mind, but the downside being that the power capacity of the trans is around 450. I estimate that I will be in the 450 range at the tires with my setup, and the vehicle is heavy and does pull a car trailer around with my 68 Skylark on it. The other nice feature is the 6 spd VS the nv4500 5 spd.