The following is a dup of my e-mail reply...
I've done all that stuff before and I've done it both ways in different cars over the years, first time as a teenager in the '70s on my 'old man's' car. hehehehe.
Anytime you pull the timing chain on these american built V-6s & V-8s, You'll damage the front section of the oilpan gasket. But that section, by itself, can be replaced when reinstalling the timing cover. This was a pretty simple thing on the older cars that used paper and/or cork gaskets, BUT --- It's really a different story with the newer rubber (oilpan) gaskets. It will be tough to get it just right... Therefore....
I'd highly recommend pulling the oilpan at the same time as you pull the timing cover, replace both gaskets (timing cover on first). The rubber oilpan gaskets on these V-6s are good but may get a little out of shape for some unknown reason. Any reason to replace it is a good one. Be sure to get a rubber replacement for the oilpan; the timing chain cover/water pump gaskets are paper.
You'll need to pull the starter and the front section of the exhaust (Y-pipe) as well as the dust shield (thin piece of sheet metel that covers the bottom of the fly-wheel). The dust shield is held on by the two starter bolts and one small bolt on the other side of the oilpan from the starter. No need to lift the motor or mess with the motor mounts either! NICE!!! With the dust shield off, you can align the oilpan easier when you put it back on. Get a good light under there and look around awhile. The new oilpan gasket should come with four (4) guide pins too; use'em [in the pan bolt holes about three (3) holes from the end at each corner] along with plenty of Blue RTV to ensure a good seal.
So, pulling the timing cover??? I'd recommend (if it were me) replacing the water pump, timing chain & both gears and every belt and hose under the hood at the same time; one big nice job that, in no way, (if done carefully and correctly) will have to be re-done anytime soon. That's just the way I (try to) do stuff...
Good luck and I hope this helps,
Any more questions, just holler!
P.S. Safety First. Always use jackstands !!!