I've been trying to figure this out recently too. As far as I can tell, the rear suspension upgrade and improved shock seals are only part of the "special edition" kits. I get the impression that the other parts have been rolled into the standard kit (beefier shock tower mounts etc) but it's luck of the draw whether you get one of these - depends how long it's been sat around in the model shop.
I just bought one and it doesn't have any of the uprated mouldings. But I got it cheap, so am certainly not complaining
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