One thing to look into is whether or not the '03 has had the injectors replaced. If it hasn't, they're going to fail anytime. That's a good $2000 hit if you replace them yourself or more if you have to pay a shop. If they have then you're probably in good shape for a while.

While I loved my '02 6-speed truck, I wouldn't trade my '03 for anything, except possibly a Mega-Cab.