Thanks for the input guys.
You say "conversion" tail housing, makes it sound aftermarket. Will a GM truck tail housing work or is the output shaft on the G8 different?
Yes, you will need a high hump. My transmission was way to low even when I had it jacked all the way up and hitting the cab floor. I moved the motor back 3.5 inches, installed a high hump and now it fits perfect.
Apparently I have the 3" forward version of the adapter plates (CPP's first design) which causes the DT 1 7/8 primary tube headers to contact the top of the tubular stands. So I got the grinder out, assuming I'd just have to knock the edge off of the top plate of the stands but no, by the time I was done grinding I was into the tubes and realized this ain't gonna work! After many calls to DT and CPP I've discovered that the original (3" fwd) adapter plates from CPP will not work with the larger tube DT headers. Jamie at DT said not to worry, they'll send me a different set of headers as soon as I call. CPP (that advertises this combo to work), on the other hand, keeps using phrases like "that's unfortunate" and "I'm sorry for your situation" instead of "how can we help"? Cool part is that I've spent $560 with DT and $4,694.44 with CPP so far
First pic is how far back I got the motor (you can just see the extent of the grinding), other pics are of another build on this forum with 1 5/8 DT headers that I think will work. Opinions?