real boost guage, manual boost controller, free flowing filter, cut your air box up a bit, cut off that tube that is inside your intake pipe that is blocking flow, clean your intercooler out, make sure your i/c piping is all tight, new plugs(properly gapped), set your base timing, make sure all your regular maintanance is done(all fluids etc). fix any boost leaks.
If you still have any cash left(and you should if you can do any of this yourself) get a local person to fab you up an upper i/c pipe.
Oh, and run 94 octane Chevron gas. Most people will overlook this part when just starting out.
Next on your list should be some sort of logging software.