As far as we've been able to tell, the tooling for IHC's heavyweights was newly developed and not previously used for another company's product line. A few of the car types will appear similar to Rivarossi's models but, when compared side by side, they are different models. It is, of course, quite possible Rivarossi's models may have provided some "inspiration" when the tooling for the IHC equipment was cut. Given the amount of supplier and tooling crossover between importer product lines which occurred over several decades, tracing the origins of some of these models can be a very challenging task.
I love that carded brass rail switch still mint in the AHM packaging. Keep that just as is for an interesting conversation piece.
Bob
