Are the pickguards for fender standard 5 string basses different in dimension from standard 4 string basses? I would imagine the pickups and the heel to be wider for 5 stringers...am I wrong? If they are different, where can one find replacement pickguards for 5 string fenders? Also, how are the stock bridges on the standard 5? Are they as poor as the standard 4? What are good replacements?