speaker wire 96 avenger?

I found some wires in my 96 avenger under the seats that look like they might be speaker hook ups but then I also found the same wires on the dash about an inch away from the windshield.  they are in these holes that are covered by a plastic lid. 

I was wondering if I could connect speakers to these and what size hole is in the front by the windshield.

Do they have plugs on the end?

I have 61/2" speakers on the doors and 6x9's in the rear. but I don't know if there ever was supposed to be tweeters in the front by the windshield.

no power seats

I'm pretty sure that there are wires run up to the top of the dash, just under the windshield.  You should see what looks like a speaker grill, but it will be covered with some kind of insulation.  The whole thing pops out and if there were a tweeter there it would also snap out with the grill.  It's a 2" tweeter and like I said there should be wiring to that location.  In my 96 caravan, which we got without the infinity system, the wiring was run to all of the infinity speaker locations; I have yet to really figure out if it's series or parallel wiring, but right now I have 8 aftermarket speakers all running off a pioneer head unit.  I just used a standard chrysler harness and used the existing speaker wiring at each additional location, and it's never skipped a beat so I see no reason why it would be any different for you.

The wires under the seats are probably for power seats, as they run the same wiring for all of the cars regardless of whether or not you actually got the car with power seats.  there are not speakers on the floor or anywhere near there really.  Even in a vehicle with the infinity system there's only the 6x9s for the rear, which you've already located, so these mysterious wires can't be for the rear speakers.

The info I have says that there are spots in the dash for infinity speakers, 4" football style; the lower section of the dashboard, one on each side, approximately in line with the tweeters. I would assume the wiring for those spots exists as well, and apparently a 4" aftermarket speaker with a modified bracket will fit in that spot.

thanks ethan, so you say that 2" round tweeters go in the front under the windshield?   and I will try to locate the 4" football style speaker space.

By the way where did you find this info?

Thanks again.

2" round tweeters mounted directly to the speaker grill.

The specifics about the tweeters and the front speakers came from the Scosche Autosound Encyclopedia.  My work pays for the monthly subscription to the service.

Everything else is stuff I've just kinda learned over the years.