[AAIIIC]

Rockie, please find the punctuation keys. Your posts are hard to read.

Did you see the thread over on ls1tech? Tons of info there from folks who have actually completed the swap.

 

[AAIIIC]

Can I swap the rear cradle of a 2009 cts into my 2004 cts v will it bolt right up

Seems like you'd want to ask in the V1 forum, since the V2 owners probably aren't swapping their drivetrains into V1s.

If you had searched for "cradle" in the V1 Performance Mods forum, you'd find this thread: https://www.cadillacforums.com/threads/v1-to-v2-rear-cradle-swap.1096757/. And if you go to LS1tech, or to the V1 FB group, you'll find plenty more information about doing a 2nd gen rear cradle swap into a 1st gen.

Edit: I'll move your post into that thread I linked.

 

[AAIIIC]

Is hub to hub measurements the same on both?

No, newer rear is wider.

 

[AAIIIC]

I wanna swap out the v1 rear end with a V2 rear end and wanna know what was needed to do this swap

I merged your thread into the existing thread that you should have found if you had searched. As stated above, in addition to the information in this thread, you can also find information in the CTS-V forum on LS1tech and in the V1 groups on FB.