no real problems. I never take the rear off just loosen things a bit to slip the belt through
looks like its fitted with the new motor so check the motor pulley. There are 2 types of pulley with different shaft sizes. later one is available but early one is obsolete and Hotpoints answer is change the motor. There is another pulley you can get that fits to make life cheaper
belt on later motors is also spring tentioned
also when putting belt on make sure it misses the screws on the drum as it wears out the belt
Dave