battery change proceedure for 2006 buick rendevous

Hello' my father in laws battery needs replaced on his rendevous,it looks like i'm going to have to remove some stuff to getit out! I'm looking for some guidance.......thanks!

I have a 2002 CXL that I replace the battery in. I had to remove the left side cross member support bar (2 bolts) and I believe had to disconnect a wiring harness for clearance. I installed Autozone's biggest battery for my car which is bigger than the OEM version. It went in only way, but went in. I'm not to car savey but found this one not to challenging.