lc 3 headunit convertor to rca

Stats: 2x - 275w 2 channel DVC 2/8ohm crossfire 12" subs              (DVC=series,speakers=parallel) 1x - 300w 2 channel 2/8ohm jensen amp 1x - 200w 2 channel 2/4/8ohm crossfire amp 1x - LC-3 headunit convertor to RCA 1x - stock 2007 chevy silverado classic head unit with wires directly to the truck's stock speakers I ONLY have 1 amp hooked up at a time! I'm trying to hook up the LC-3 so I can convert my stock headunits speaker output to RCA so I can hook up my amp to my subs. I'm wiring the left LC-3 + and - wires to the headunit's left rear + and - Then right rear to LC-3's right + and - but I'm getting no output from the LC-3! I know its the LC-3 cause I verified with a dvd player's RCAs and the whole system works fine! I've even tried reversing the polarity in the connection from the HU to the LC-3's wires and still no output! (I was told to do this and was told that all 4 LC-3 wires HAVE to be hooked up) I've tried changing the HU's balance. I'm only hooking the amp's remote 12v DC+ input to the 12v DC+ from the car battery to get it to come on(as a temp until I know it will work) 1) How do I get the LC-3 to work?

2) Is it ok to have a 300w 2 chan amp on 2x 275w subs?    (I've done it before with no problems, just keep the gain down) Thanks!

what the heck is ONE of the HU's speaker output voltage supposed to be? I get like 20.0 mv at the max! (when in use) thanks

Is there a BOSE logo anywhere on the front of the radio, or on the front speaker grills?

i believe stock head units should put out 2-3v on each speaker?

oh sorry there is no BOSE anywhere

I really cant find a pic of the LC-3 and I dont know who makes it but it looks like this: http://www.amazon.com/Scosche-2-Channel-Adjustable-Lineout-Converter/dp/B00009UHRE/ref=sr_1_1?s=automotive&ie=UTF8&qid=1320638782&sr=1-1 I think its a problem with the HU's output though, it should be 2-3v and I'm only seeing like 20mv

I couldnt think of anything @ the HU to help. I think that all the wiring schematics I've found are wrong even though they really look right. I came up with a solution, instead, I'm going to tap into the actual speaker area so I KNOW for sure that I've got the right wires. I bet that will fix my problems and I'll find my 2-3vs! thanks for all the help!

That surely did fix my problem, the wiring diagram was just wrong! Plus it still giving a sup low voltage (like 20mv when it should be 2-3v)   but it works now! I'm wondering, if an amp says its a 2 channel amp @ 300w and you have 2 subs which say they are 275w. Whats the best way to set it up? I realize I want the lowest resistance that it will allow so I went for the 2ohm set up. but if the amp is a 2 channel @ 300w does that mean 150w per channel or does it mean 400w in total when bridged? thanks!

Does the amp say 300 watts x 1 into 4 ohms? 

No it does not specifically say that! Are you trying to tell me its 300w into 2 channels so really 150w per channel? Each 12" sub says "275w" so I'm thinking it can handle more? I've even put more through it and no problems... didnt seem like it had any more power but I never really turned it up!1