Possible, yes, easily, no.
I replaced an optical drive in one of those, and unfortunately it takes a fair amount of work to get into. Also, because the bottom base acts like a big heatsink, there's a heat pipe that is thermally "attached" to the bottom base. Because of this, if you're going to take it apart you should probably re-apply some thermal paste to this before reassembling, lest it overheat at some point in the future.
It's nothing someone with a steady hand and a basic understanding of the guts of computers can't manage, and if you have or buy a little tube of thermal paste (from RadioShack or any moderately geeky retailer) and the right set of torx bits, you can probably manage without breaking anything.
There are several walkthroughs that Google will lead you to--have a look at one, see if it looks like something you're comfortable trying. If so, it'll tell you what all you need.
