What is the difference in generation 1 and generation 2 rear knuckles

Hi Kris, Why are you looking to switch out the knuckles, if all you need to replace is the rear springs and struts? I would not try to replace the knuckle unless there's a good reason for it, particularly since it is not the exact match. You could be opening up Pandora's box by doing so. Proceed with caution, please. Regards, Interstate Auto Care customer care team