2003 chevy tracker help?

i got a chevy tracker 2003 2 door convertible 4 calender engine with a prndl(aka automatic transmission ;) and i have a few questions that i need to be answered... the first question is that im adding a sub but that the easy part the problem is i want to keep the car as stack looking as possible. there are some spaces ware buttons/switches/dials/nobs could of been i got some photos of the areas ware i need switches to be i numbered the ones i didn't know in blue and the ones with red leters are the ones i'm not there if a switch was sapos to be there or that how it sapos to to be and the ones with yellow ( ! ) is ones that are there. if you know what one of the switches are put "(*)" replacing the star with the number or later of the space and what it is next to it.

the secant thing i need answered is that i have this plug at the front of my tracker that apparently hooked up to nothing idk what it ther for or if i need to plug it back into somthing i couldent find anything about this plug on the internet and i'm thinking that it could be an add on that you could buy from the dealer but if that is true i'm not shure. if you know what the plug is for put "plug;" and write what you think it is.?

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