So I am currently shopping for a turbo (first time i ever do so) I found a local shop that sells rebuilt turbos (blaast performance) and would like to buy one of theirs but I have 2 questions

turbo is a

T3 / T4E 57 trim
compressor wheel: 56.6 / 74.9 mm 57 trim
compressor housing: T04E 0.70 a/r, 4" / 2½"
center section: oil cooled journal bearings
Turbine wheel: 68 trim (stage1)
Turbine housing .63 a/r, 7 bolts outlet flange

and for an extra 30$ they offer a "block off flange"

description

"Block-off flange (7 holes)

With this very convenient option,
We will install on your turbo a 3/8" thick, laser-cut, mild steel downpipe weld-flange that is acting as a Block off flange to disable the internal wastegate bypass in order to use an external wasetagate."


So my two questions are

1. block off flange will just make it so i can just use an external wastegate instead?

2.Outlet flange is 7 bolts.....does that mean i have to find a 7 bolt downpipe? (sorry im still learning how to piece together a kit) what kind of downpipe can i use? because everywhere i look for a turbo downpipe it says most of the time 5 bolt....on a quick google search it says i would have to get a custom one made

 

pics of said turbo