458 Replacement bolts for engine bay?

I am about to embark on some detailing work for my engine bay, and I noticed quite a bit of rust on the bolts around these two areas (symmetrical on each side), but I have no idea what these are and if I can get replacement hardware for them (ideally in something that won't rust). Does anyone know the name of them, and/or the size of the bolts, and if this is something that is OK to replace.

Also, for this cleaning, I wanted to pull off any pieces that come off easily to do a deeper clean on them, but couldn't find any great guides on this. Any pointers would be welcome here
Image Unavailable, Please Login Image Unavailable, Please Login