no, you won't need to drop the tank, I would run different line to and from the pump though. If you get a vulcan big fuel line kit, or any other big fuel line kit, it should have all the necessary fittings to connect at the tank and the stock lift pump. then it is just a matter of splicing in your holley black pump.
How much is the holley pump? the line kits are roughly $250 so add that on top of your pump and then you'll have the total. I would consider running a better fuel system, like a FASS or A1000 or RASP or something like that, they are a little more expensive, but give you the protection of a much better filtration system, and most will also remove any air from the lines. I noticed increased milage by 1-2mpg (Hwy) with my FASS.
On a side note. I am running the Holley Blue and have been happy with it. It holds great pressure with my mods and cost me about $90 at advance auto. I installed it with a lift pump relocate kit from Vulcan. Here is a link to the kit http://www.vulcanperformance.com/servlet/the-12/<i>Vulcan--Pusher-Pump/Detail . If you have the money get the FASS if you are looking to save some money the Holley is a good option.
A forum community dedicated to Diesel engine owners and enthusiasts. Come join the discussion about performance, builds, ecodiesel, towing capacity, modifications, classifieds, troubleshooting, maintenance, and more!