Steering rack replacement/2002 Ram 1500/4x4

I have a 2002 Ram 1500 quad cab 4x4 that has a leaking steering rack.The dealer's shop tells me it has to be replaced. The estimate is 920 dollars to do the job.I was wondering if someone has done this particular repair and what is involved in removing and replacing rack unit,wheel alignment, etc..If so would you please reply? I'm trying to determine if I'm going to repair it myself or have the dealer do it. Thank you in advance for your help.