Great model. I'm sure you're aware of a resin kit of the engine for this model. If not, here's a pic and a link. It's a shame that they didn't include the diesel that drives this beast. I'm biased towards models with engines. The model also includes parts to modify the Hobby Boss chassis to accommodate the engine and air intake parts.
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And here's a link to a review of the model and contact info for the Real Model model.
militaryscalemodelling.com