I recently changed the brakes on my '42 B. First time ever for both me and the tractor. No particular trick other than soaking the anchor and pivot pins in penetrating oil and planning on a frustrating time getting the old bands out. Actually the pins came out easier than I expected with the help of a zip gun. The bands were more difficult than I expected. They certainly needed to be "persuaded" with quite a bit of brute force to get them out in the space between the drums and the final drive housing. Even the new ones needed some hammering to get into place. I would up using a slide hammer to remove the old bands. I have heard that some have used an engine hoist to pull them out. In any event, pulling on the front and pounding on the rear of the band assembly was necessary, at least for me.
I recommend you consider the condition of your existing bands before deciding on replacement vs. relining. My existing bands were badly deteriorated by rusting and were not suitable for relining, IMO. In my case, replacing the entire band assembly was the best course of action.
I now have brakes that actually work :o).