Block casting protrusions

[Breitenbucher]

Since my block is very rusty and I didn't want to sand blast due to fear of getting sand where it could do damage I'm using a Dremel tool and small grinding stones to remove the rust from all the nooks and crannies before painting the block. This allows removing and smoothing the side walls of all sorts of rough stuff left over from casting it and rust pitting. However I have come across several protrusions as shown in the picture that I would like to grind off but want to make sure I'm not causing harm to the block. Not sure if they are left over from pouring the casting and grinding them off may leave some kind of hole. Anyone have advice on this?
Thanks,
Paul

[Deve]

I am just not sure myself. I would leave them. It is probably just casting mold alignments or something, but on something as rare as one of these engines I just wouldn't chance it.

[Breitenbucher]

Ok, I will leave them. In fact I just got in some small buffer 120 grit sanding wheels for my Dremel that will buff out around those protrusions and also remove those grinding scratch marks. I hope I haven't alarmed the purest out there (just want a good paint job to protect it) but this engine is just going to replace a mid 40's Stovebolt in my home built forklift my dad and grandfather built starting with a WWII Chevy Army surplus truck.
Thanks,
Paul