The two posts above pretty much spell it out. Verify about your timing cover gasket. Watching the coolant level? Well, unless you want to check it every time you get ready to drive it, I'd say you just get in and go. If something fails, well it failed. You could worry yourself crazy (sounds like you are) over some of these issues.
Yes, from what I have read, the early yers had some problems. But, not all will fail with these problems. My truck (2000) has 80,000 miles on it and it has never had any problem (other than the long ago removed factory cassette deck).
So, monitor what you would normally monitor, change you oil, air filter, plugs, etc. as required and just drive on. you already own the truck. RELAX and enjoy it!
Otherwise, sell it and buy something else. Life's too short to fret over what MIGHT happen to your truck engine.

Brian A