The standard inner diameter of that fitting is .175" for reference.
The top brass fitting is a 1/8"NPT street elbow (M/F) that I will use to angle the straight fitting correctly.
On the lower left is the blue fitting that I talked about above. You can see the set screw screwed into the fitting and a bit of the surrounding anodizing filed off (just to make sure there were no burrs, I cleaned it up). On the lower right are 3 of the same set screws to the one in the fitting.
The reason I went with the set screw over a washer or something like that is because I didn't want to deal with making 100% sure it was sandwiched properly, or possibly suffer it breaking up and entering the turbo (bad). Also, I put it on the feed side of the fitting versus the end towards the turbo because the pressure will always be pushing it more into it's thread (which is only threaded in as far as the screw is deep).
Now I just need to drill a hole through it and I'll be good to go. The set screws are probably hardened just enough to make it tough, though. *shrug*
In retrospect, I probably could've used a #10 set screw instead of the 1/4-20, but I wasn't sure that I had a tap for that size, so I ended up drilling out the fitting slightly to get the tap to work correctly.
Also, as it sits, I can drill it out probably 1/8" and still use a hex key to change out that set screw since the drill fit inside the socket without messing up the edges.