Thanks cfischer... haven't used those two yet (though they are in my bookmarks). I've been looking up flights on kayak.com and flightstats.com... but since I'm not really familiar with all the possibilities in South America, I thought, I ask here.
And a connection of one hour on different PNR with getting my backpack and checking it in again... that might be a hell of a challenge :-) Those LAN and TACA flights should be half an hour or an hour later, and they would be perfect.