why is it worth risking stripping out the aluminum threads, braking the bolts when trying to take them out considering you are having a hard time removing them. you have everything to lose and nothing to gain from this unless there is more to the story or I have missed something here. you may end up having to drill out, and install a helicoil, are the bolt comprimised in anyway?
just my 2 cents here, best of luck to you, all the previous suggestions by the fellow beullers to remove are good ones, I just do not see the need to remove them.