i think the v6 might have had a smaller trans, but the one that cam behind the 4.8 is a pretty decent trans. I have on win my shop from my truck. It will be a huge hassle going from auto to manual. you will need pedal assay, master cylinder and accessories, diff cross member or modify yours, pilot bearing, clutch setup and flywheel, and of corse cut a huge hole in the floor. speaking from experience, stay auto unless you go with a good trans like a t-56. just my .02