I just bought a LS1 DS for 75 on craigslist. I need to know which end should i jack up and put stands on. Also, is it difficult?

 

Jack it up from the rear. Just remove the 4 bolts from the straps holding the rear u-joint and push the shaft forward. Slide the old shaft out of the transmission and then slide in the new one and reinstall the bolts. Jacking it up from the rear makes it easy to get to the bolts and keeps transmission fluid from leaking out.

 

Don't over tighten the U-joint bolts. I can't remember the spec off hand, but it isn't much.

Rich