It's not too difficult. Chase the threads in the frame holes you'll be using - they're probably dirty and corroded a bit. It'll make running the new bolts in a bit easier.
Also, a buddy to help lift and manhandle the sliders is nice. If you can't find someone to help, have some jack stands or, depending on the lift and tire height, a couple five gallon buckets to sit the sliders on to get them elevated and close to in position.