I believe the water pump on my dad's 150k 2.7L Intrepid has bought the farm. Come to find out it has been losing coolant for a bit (wish he would have mentioned this). It was running real rough the other day and he checked the oil and it has coolant in it. Could also be a head gasket I'm guessing. Hopefully not too much damage has been done, the engine had ran well otherwise.

If it is the water pump how crazy hard is this to do? I would consider myself "ok" at best at turning wrenches, certainly be no means an advanced mechnanic. Especially so on the newer stuff.

Any tips or words of advice?

Thanks in advance!

Don't drive it at all till it is fixed! Those are VERY delicate engines.

It is not too hard but plan on all day the first time you do it. I like to zip tie the timing chain to the gears before removeing them so I a positive they go back exactly where they came from. You can do them with out pulling the radiator and core suport but they are easy to remove and make the job much easier. Also make sure you have a good 3 jaw puller before you start and it has to be kind of small to get in there. Take your time and make sure you get it sealed properly. I replace the tensioner as standard procedure now

Same as Dave said plus make sure you flush out the oil pan extremely well, I've found also that synthetic oil tends to lessen the problems with this engine as it doesn't tend to sludge up like normal oils.

I assume you know but a leaking water pump will not make it run rough.

IMO, if it runs rough and it's loosing coolant I would look closely at the head gaskets.
The timing chains can and will be very intimidating to those not familiar with the 2.7 V6

they're not super hard but definitly up there and will require keeping your mind in the game while you have it apart

If it's worth head gaskets, now is the time to do the pump.

You should try to figure out if it is only the water pump or if it is head gaskets as you would spend a whole lot of work and effort to just do the pump. There is a weep hole that can be seen from under the car which will indicate a bad water pump but you should verify head gaskets are not leaking. If they are it may not be worth the money and effort to repair, especially with 150k miles.
I did a water pump repair and it took about 10 hours and cost about $200 as I bought a new chain tensioner, new pump, front cover seal kit and valve cover gaskets. I used the manual which helped alot.