Parking brake cable retainers & grommets?

Have just gotten replacement cables for my Cuda and am now looking at all the retainers and grommets. The YearOne catalog has a firewall grommet listed, but the thing is 21 bucks! Is there an alternative? Also, does anyone know exactly what the set up is supposed to be where the front cable passes through the frame (under driver's door area)? My original stuff is gone, and the new cable has no attachment hardware or anything. The rears have retaining clips and seem pretty straightforward, but I'm a bit confounded by the front. I really don't want to jerry-rig it. THANKS!