Originally Posted by schang

Also, rear wheels can be a pain in the butt, and you will have to get your hands a little dirty especially if you have not done it before. Just remember that the rear derailleur can be swung at two pivot points, both at its joint with the frame, and also the sprung derailleur arm joint. If you work these two joints to open up the chain, then get the rear cogs between the chains, and keep the derailleur from blocking the dropout, then you should be ok.