Rear sprocket bolts are stuck

Hey Viffer Nation,

I'm in the process of doing my chain and sprockets. My rear sprocket bolts will not loosen. They will "break" loose but just turn the bolt with the stud.
Has anyone else had this happen? I don't want to put a vice grip on the back of the stud to hold it and chew it all up, but I don't see any other solutions. I am going to spray the bolts with pb blaster tonight to try and loosen things up.
Thanks in advance for your advice.

 

On my 5th gen there are hexes on the back if the studs. Had to use an Allen wrench from the back.

 

Same with mine.

 

Thanks they are so dirty I didn't see them but I had the rear wheel on too. I'll take the wheel off. Thanks.