Id like to replace the mount but i couldnt remove the bolt. It wont budge. Should i be turning the nut instead of the bolt head? The nut has this metallic tail-like stuff in it thats getting in the way of any wrench i throw in. I dont have advance tools jut the basic wrenches

 

Turn the bolt......

EDIT: found a pic that might help explain why, see the "tab" on the nut, the tab "locks/holds" the nut.