I have done it, it's not hard at all if you have the small hog rins pliers and hog rings. You just have to work it slowly because the middle lumbar section is tight as all get out and you don't have much space to latch to the wire that runs across the middle.
There is a trick to the headrest covers, but you don't learn it until you're done the 2nd one, lol. You place the metal bar in, get one corner in, twist the head rest cover almost sideways and then mash the pad down with your knee while you twist the head cover on and then massage it on once you have it all the way around.
If you take the seats out, most shops would charge you ~$150.00 to do it.