Replacing the Rack and Pinion Assembly on a 87 Dodge Dakota

I've got an 87 Dodge Dakota with a 3.9L V6. It's got a power assisted, rack and pinion steering unit that is leaking. I took it to a shop and they said that it can't really be serviced so they would have to replace it. I don't want to spend $300 to have them fix it when I know I can get an after market assembly for less than $100. Trouble is I don't know how difficult it would be to replace it myself. I've done minor replacements in the past for things like belts, hoses, alternator, air pump, ect. But if it's something for which I will need special tools or special knowledge then I may not want to tackle this myself. Basically, what I need is for someone to tell me either, "yes, this is something that you could do with a little research and assistance." Or "don't bother, it's too complex."