as far as guages id just get an oil pressure gauge, boost and wideband.
-boost controller (i prefer electronic, either will work fine, but if you do get a manual get a joe p)
-turbo depends on how much power you want
-anything bigger than a 16g you want an external gate
-255 fuel pump will be good
-id get a AFPR with that, but you dont need it
- injectors- once again how much power do you want?
-flywheel only if you are gonna rev the car high
-intercooler spray- just get methanol injection, youll be glad you did.
-exhaust manifold, id keep the stock one and port it out.
-intake, just get whatever, its not gonna make a difference
-motor mounts, yes you want those
- get cams if you want a good powerband some BC's probably 272s
-fuel rail, NO the stock one is fine for any power basically
-spark plugs and wires, just get ngk bpr7es
-ignition system(i have no clue what that is, at the most get a coil on plug setup, but i wouldnt worry about that too much right now)
- just get some eibach springs and put em on some kyb struts
-electronics-DSMLINK!!!!!!!! DO IT! it will let you read intake temps too, so dont worry about those guages.
-as far as spoiler, do what you want with that, personal taste there