Plurr nailed it right on the head. Using the same hole he did is really easy. First I ran a small, rigid, pull wire (like you'd use to hand ceiling tiles) through the hold to see how I came out on the other side, and I folowed that same hole and enlarged it with a large philips screwdriver (all of this from under the dash on the driver'* side). Then, resinserted the small, rigid wire, made a loop on the end, criped it to the wire to pull through, and pulled it through. It'* a tight fit because there'* so much rubber, but it'* really quite easy.
'95 SSEi, few electronic mods (and a stupid coupler)
HU (Sony MDX-CA680, European Ver; Sony 4x3-ways; 91, 93dB)
Yup, that'* ISU