If you are doing suspension mods for off road, look into Deavers to help with the wheel hop if you ever smash the throttle on the pavement. It wont stop it entirely if you are on aggressive 37 or 35 inch tire, but it helps a ton versus stock leaf. Also, If you plan to run in the dirt more, don't do a traction bar. They just don't let the rear end move enough off road. Great for a street truck though.
I had a tune done by Jim at JDM but I was on TVS (Roush) not a whipple. He still has a ton of tuning experience with either, so I would not hesitate running his tune on a Whipple.
If you are doing the build yourself, take a bit of extra time and pull the front cover while the truck is down. You will have so much of the truck apart to do the install, that you might as well do the oil pump while you are there!! Doing it after is a major pain.
Melling has an upgraded "drop in" oil pump, or you can get the billet gears from multiple places. I did not do the gears as my truck was a factory built blower truck, so I never had it apart. But the thought was always in my head to do it if/when I ever needed to freshen up the engine.
I assume the Whipple kit comes with injectors, gauges etc. so nothing should be needed there.
Transmission likes a converter from Circle D, but stock works fine. The tune is critical here to make it drive well and hold the gears longer.
4:10 gears are fine on 35. Good idea to re-gear on a 37 (4:30 or 4:56), but the extra HP a blower provides, makes the bigger tire work with the stock set up.
The stock exhaust will work with the blower, you will probably want to get less restriction though. Most of the supercharged trucks I have seen work well with the resonator gone and a straight through type muffler