Do the drums rotate? If so, your main problem is to separate them from the hub. There are two screws that hold the drum against the hub. If you can't get them out, driill the head out and leave them there. They are not really needed. You need to smack the drum where it rests on the hub, with a good hammer. You will see clouds of rust start to form and you will be able to see slight movement at the drum surface at the axle. Once you can actually feel some movement, pull on the drum while tapping the edges. Although some of the vendors list new drums for the 3/4, I would be very careful until you find out if they are in fact available. If it was a 1 Ton, you would not be able to buy a new drum for sure.
