Here's my 3" spindle

 

I put a jack under the lower control arm and after removing everything around the spring I slowly jacked it down releasing the spring. Take the spring out and place the spacer on top. This is when you'll want to compress the spring so it fits back in. Reassemble everything and go for an alignment. You will need to buy a camber kit for the upper control arm so it can be aligned correctly. I'm willing to bet you will need new upper and lower ball joints as well. I thought mine were fine but the shop doing my alignment said they were shot and they wouldn't be able to align it. So I had to pull everything apart again and replace those just to get it into drivable condition.
The price to have a shop do everything I just listed would be close to $1500. You can do it yourself for under $500 but you have to be sure you know what you're doing.