There was no Prewar unit, and several different postwar units. May want to narrow a bit what you're looking for.
2333: has ladder grabs and ladders added but no magnetraction
2343: Same as above but with magnetraction
2353: no more added ladder/grab handle details, but still magnetraction
2383: No more porthole windows. Still dual motor/magnetraction, but exterior is much less attractive/detailed without the grabs/ladders/portholes