You could put a 4# pulley, a cold air intake and a tune, but personally, I would not start beating on a 61k engine without some serious upgrades. This would also depend on the level of maintenance and upkeep on said engine. Before you do that upgrade to a pulley/tune, make sure the intercooler is clean, the intercooler pump is functioning perfectly, a new fuel filter and a plug change for starters. There are smarter guys than myself who can offer more guidance for you and hopefully, they will chime in.
BTW, these changes will create a domino effect and your pocketbook will suffer immensely, just a friendly warning.
I second what FirGuy wrote. I have a 2000L with 64,000 and it's a daily driver. You need to make sure everything else is in proper working order before you start throwing more power at it. I learned a few things the hard way. There are lots of threads that will help you out with anything your wanting to do or learn about on your truck. A 4# or a 6# lower pulley would be fine on your truck with a good tune. By the way nice looking truck.
This is a good article with tones of information.
Lightning and HD Modding 101 - Superchargers