8 speaker celica head unit upgrade help!!! Options

[chris32880]

Hey guys I upgraded my speakers with pioneers, 1 inch tweeters are still stock, the 4 inch top speaker on door are pioneers, 6.5 in back are pioneers. I just ordered 8 inch 400 or 450 watt 8 inch speakers, the speakers weren't a problem at all, now I want to do a double din pioneer head unit, I need to know if I have to buy the plastic for it to go in like a single head unit needs... The celica 8 speaker runs on 2 amps, I found the metra adaptor for the amps to be used te double din head unit I will be using has 2 RCA plugs the adaptor has 4 I need all 8 speakers to work so I need install help I found a forum with info but want to wire everything perfectly and need to know if the head unit I'm buying has 2 and the adaptor has four if it will work or not thanks any feedback will help

[mkernz22]

You should wire the door subs to either the RCA speaker output or the sub output. The tweeters and 4" speakers are tied together so it's technically just one channel.
I'll double check how mine is wired in once I put it all in tomorrow haha

Do you still have the stock head unit? if so, how much would you want for it?