Oil fouled carburetor...

That appears to be dry soot, not oil. Unless it is wet and slimy, which it appears not to be, it is soot.

Maybe a little soot is normal, but not that much. Looks like it is running rich. That means too much fuel. If you go on the Holley site, they have tuning videos that can tell you how to tune a Holley carburetor and what to do in the proper ORDER. That is very important. Failure to make adjustments in the right order will throw it all off.

Not trying to blow you off......but by going to the Holley site, you cut out the middleman and you have a much better chance at getting it right. Here is the link to their videos. Scroll through them and find the one that best describe initial tuning and go from there.

Carburetor Installation And Tuning Blog Posts - Page 1