It's not a good idea to reuse bolts that have welded themselves to the thing they're supposed to be holding together. And it's just easier to buy new ones and ruin the old ones. I had to do the same when I went to fit new LCAs at the back.
Obviously you won't have to grind the arms I had replacements so I didn't care... but it's quite easy to trim the heads and nuts off if you're got steady hands.
ended up taking it to a garage as i didnt have the tools to do it front two were easier with an air gun but the back two we had to chop both ends off and drill through was a right night mare tryed everything they had aswell but that was the only option in the end
I had to do the same thing with my rear suspension on my EK4. the head of the bolt broke off so i ended up grinding off the nut on the other side. taking the LCA off and used a press to get the old bushing out and a new 1 in. pain in the arse job, but it's all sweet now!
Yeah, having worked on old VW's there is only one way to remove stubborn bolts...heat! Never force a bolt otherwise you'll either snap the head clean off or round the flats, then it's a real PITA! Soaking with Plus Gas over night sometimes helps, but I always reach for the gas. But be careful with the flame ;-)