Sorry we havent updated the website in a while but here goes, you dont have to buy a seperate compressor housing to make it bolt up, when you buy one you have an option of 2 compressor housings.
One (the original style) requires some mods to bolt it up to a stock truck because its hose out. The other style avaliable is vband out and will hook straight up. With a downpipe this turbo is pretty much bolt on for the 2nd gen trucks with the vband housing.
As for avaliablity they will probably not be avaliable again untill the middle of next month. We are slowly getting some parts in but most of those are going to back orders.
hope this helps
jason