You are correct on the Omni kit. Enjoy your new suspension.If I have rust all over ANYTHING stock, I'll be pretty damn disappointed! Hahaha.
I think the Omni-Kit is just a couple of machined sleeves to make the smaller-diameter lower end of the early-model shock fit in the larger-diameter seat on the late-model spindle.
But I also didn't know that the late-model springs are progressive and the early-models are linear, so I'm willing to bet there are plenty of other things I don't know. =P