What's the difference between the 2000 EX and an SI?

I know the SI has the B16 and a lower geared tranmission, and then I think I saw they have different springs/struts and a spoiler... but anything else?

Also, a b16 from a 99-00 SI should drop into my 2k EX with just a rear motor mount change and the ECU/shift linkeage/axles from the other car, right? Will it also be emissions legal?