N14 Celect Plus Practical Power Upgrades

I have a 1999 9400. I bought the truck with a bad engine (N14 C+) and planning on doing a swap out of another truck with the same motor and building a heavy haul tri axle. My question is what power upgrades can be done to take my 435 hp black top to hopefully somewhere around 500. I don't want to break the bank with fuel economy or have crazy hp just wanting some practical usable hp. Thanks for any help!