Those would be just regular threaded little studs that go in to the cylinder heads (at the sides) , then 2/3 nuts just secures then down . You could slice (dremel+cutting disc) them off but be ready to buy new short threaded m6 studs , they are same as the oil filter cover if you get what i mean.
Either way , slide around the cylinders where gaskets are and pry upwards bit by bit , i am assuming the front tyre really chucked a lot of mud & salt at it, and you have a classic case “weather seizure” followed by heat of the engine , causing them to warp and get stuck in there. Go easy though as the studs are steel but cylinders are aluminium-cast metal mix !
Don’t give up yet if you got this far , if it runs in the end you will have more of a sentimental feeling over her than the new bike (possibly!)