Thread: Advice needed for burred screws. Help!

If they are beyond an impact driver probably the only solution is to drill the heads off. (You could drill them and use an esi-out, but this is unlikely to be successful; and you risk damaging the thread in the hub.)
Then after the drum is off you will have a short stub that you can slot to remove, having cleaned up the area as much as possible and soaked it in penetrating oil, which will probably work a lot better now since you can get at the back.

Failing all else, you can remove the entire hub and drum as a unit by undoing the wheel bearings, this will also give you access to the rear of the screws to soak properly in penetrating oil.

if you have an oxy set or gas torch available you can heat the screws to red hot and then let them cool. this will usually make the screw shrink enough to ease the tension on the screw. you can then move the screw with a hammer and center punch until the tension is of the screw so it moves easily.

if you dont have a heat soruce you can use a hammer and drift the right diameter to hit down directly on the screw head with moderate force several times and this will cause some of the tension to be released so you can then try to move it with a center punch