I don't think applying heat to those bolts would hurt anything, just don't go overboard and cook your wheel bearing grease. The impact gun is your best bet, just don't whale on it.

Seal needed after removal? Naw. Just clean it up good and use some black RTV. There's only grease in there, so it's not likely that it'll flow out easily.

No sweat, Hamer. Keep the questions coming.

John B.