Don't play with the bolts.
If you're not leaking, take a utility knife with a NEW blade, or a NEW single-edge razor blade, and use it to trim the excess material off - the stuff that's squidged out. Trimming the gasket will definitely be safer than trying to reassemble it - once you loosen those bolts, you're likely to lose the corner seals up front, and then you'll HAVE to change the gasket.
I don't see any contact between the gasket rail and the harmonic damper in your pics (the HD is that large pully down bottom,) so that's probably not the source of your noise. Check the belt for glazing, and check the idler pullys (there are two) and the water pump pully (all three of these are the smooth ones) for glazing as well - since that's where it's most likely to come up. Remove with a Scotch-Brite pad. If the belt is glazed, just change it (and maybe keep the old one for a "field spare" just in case.)
The idlers also run on bearings that might squeal - the upper idler has a serviceable bearing (you can press it in/out with a vice, if you have one,) and the lower requires replacing the entire bracket that supports the A/C compressor or the A/C Idler (depending on whether or not you have Air Conditioning.)
5-90