Thanks for your answers, good tips!!!

However in my case the hex on the bolts I mentioned have been completly f@@@ed, not by me btw, since I never touched them before realising this. The one on the crash panel is I think impossible to get a grab on with a vice, because it is screwed in a holow spot in the panel... I will still give it a go though... As well as the sprays...

Been doing some research at work and saw that in similar cases the bolt needed to be drilled... ?

Anyways will try everything you guys said, if it doesn't work will still be helpful for the future!