Glad to see the post is still helpful.
I've been driving 04 TSX since then which will hit 270k miles soon! Sold the Intrigue at 140k when it blew its head gaskets 10 years ago. Was told due to the bad machining in aluminum block and head for the thread holders for the bolts in the block. I didn't want to put that much cash into it at the time.
I'm fairly amazed your Olds has that mileage!