Don't do anything with the traction tires until they break. They last for a very long time. Once they break, remove any side frames or drive rods, slip the new tire on over the rim of the wheel and into the slot in the wheel. Replace the side frames, or drive rod and you are good to go. I think that I have had to do this once or twice in 30 years and I used to run my LGB engines a lot.
Chuck N
Chuck N