Im trying to change my speedo cable but cant get the front hub of the brake drum!! Car is 1970 Bug, its not the original drums but look pretty standard 4 lug drums to me. Tried lookin for the adjusters but cant see them - are accessed from behind the drum?? Dad wanted to start levering the hub off with a screwdriver and the start whacking with the mallet but really there must be a more humane solution?!?