You had to cut the master cylinder and re-weld it on to the bracket at an angle?
No no no, I'm sorry if that was confusing.
The stock f-body master cylinder has an angled mounting flange on it.
If you use it you'll need to figure out a way to deal with that flange when mounting it to your car. There's plenty of aftermarket support for it. McLeod, Detroit Speed, etc.
I found this plate on ebay and purchased it, planning on using the f-body master, it would have worked fine:
After I saw I had to cut the master pushrod and cut threads / weld / etc I went with plan B, the Tilton master cylinder. I was afraid I would heat up the brand new master and ruin it, the Tilton solved that issue.
I used the purchased f-body bracket as a template to create a flat bracket for the Tilton. Once I got it mocked up on the car, the tilton stroke is around 1". With the flat bracket the clutch pedal throw was very short.
That's when I mounted the tilton at a downward angle to give the clutch pedal enough throw. It's not perfect, some people will say it's wrong, but I've beat on it every way I can and it's still holding up fine.
If you do a search for fbody master cylinder bracket you'll find a lot of info on the web.