How to tell
 

I bought my car used, and I was curious how I go about finding what package I have. I think I have a premium or just a custom ordered. It has leather seats, 19's, shaker 500, sync, it's race red with black interior. From that is there any definite way to tell what package I have?

if you have billet shift knob its 401a if not its 400a

you can do a vin search, or carfax.

No billet, and I might run the carfax on it soon. Also are racing stripes part of a package? I have some but whoever put them on did a horrible job and they don't fold over the edges correctly.

Isn't their a sticker with the codes somewhere in the car?

Mostly like a 400A package.

Just Google search "Ford VIN Decoder" or "Ford Window Sticker VIN" and type in your VIN. That should pull up your WS and tell you what's been done.