Quick downpipe question?
 

So I am reinstalling my parts after switching to non-sequential and while I was putting on my downpipe I ended up rethreading one of the four holes that go into the turbo. Now bolt will not go in all the way. I have already bought a tap to rethread the hole. I was just wondering if those holes go though into the turbo setup, because if they do I would have to take my turbos back off because fear of metal shavings in the turbo. If I was at home I would just look but its probably going to be pouring down rain by the time I do and I just wanted to know how much work will be ahead of me. Thanks guys.

As you look at the flange that accepts the downpipe; the lower rear (closest to firewall) and the upper forward (closest to waterpump) are "through" holes.
The upper rear and the lower front are "blind" holes.
Retapping any of them will not allow shavings to enter the turbo.