I have no sound coming out of my right rear speaker from a 93 Civic EX. I've checked the restistance between the pos and neg of the right rear speaker and got a OL. I compared this to the left rear (125-126 ohms). It appears that I have an open somwhere. I'd like to hook the neg and pos of the rear speakers together and check the resistance from the terminal block that goes into the back of the stereo, but how do I get into the terminal block?