Cam help, and other questions

I am looking to put in these mods for my car.

TR 215/220 .600/.523 115 LSA Cam (have to pass emmisions...if anyone thinks this won't pass..lemme know)
New Pushrods, Vavlue Springs and Retainers.
SLP Lid
**JBA Shortie Headers (...stupid NJ)
Magnaflow Catback
LS6 Intake Manifold
**Bassani Y-pipe with High Flow Cats

Now I have a couple of questions, since I have not bought most of these mods as of yet.

1) Should I get the new retainers? I'm not really sure what these do so someone help me out :)

2) The JBA shortie headers. Are they worth it over the stock 98 manifolds if I get the cam. (aka..not as good as the 00-02). I would never dream of getting these without purchasing the Cam, so after I install the Cam, will these perform significantly better than the stock manifolds. And no, I won't get Mid-leghts since I have heard they move the Cats (atleast the MACs do..if anyone knnows if the Bassani don't lemme know).

3) Do hooker shortie headers have a CARB certifacation?

4) The Bassani Y-pipe, do those move the cats when installing it to shortie headers. If they don't, should I just get these and keep the stock manifolds or vice-versa?

5) Is the LS6 intake manifold with EGR provisions good for this kind of set-up?

6) Should I get anything else? Port the TB? New injectors?

Thanks!!!!!!

-Todd