Looks like they're the outside for that hole in the middle. How far can I go?

I read this page here:
http://www.bfranker.badz28.com/96ss/58porting.htm

But don't see the answer. He took a little off, but didn't go all the way down?

 

i just did this to mine, i doubt you're gonna find an answer for how much to take off those "humps"
i just ground a little bit on them and left them alone, didnt want to poke thru there

i dont think they will hinder performance too much

 

I'm not sure what you are exactly talking about by "humps" but if they are what I'm thinking you are thinking, these pictures should answer your question

http://www.bfranker.badz28.com/misc/monoport1.jpg
http://www.bfranker.badz28.com/misc/monoport2.jpg

 

single blade...

 

What the heck is that thing there for then? Looks like it goes from that hole in the front and then straight down to somewhere...what is it?

Yes, that answers the question that it isn't very important wned:

I got one side down, I've just been shining a flashlight in that hole and grinding away. I got it pretty much clear of the hole. Still got to do the other side.
My shopvac fits PERFECTLY inside the 58mm hole BTW.

 

I ground the bumps down even with the throttle body holes, that way the bumps didn't protrude into the airstream.