I got mine from Parts Express. I would follow fellow Tech Steve Phillips advice and omit the hold down clamps and do the following.
With forte lying on protective surface on it's front (front fabric grille REMOVED for it's protection)
Remove 4 of the passive's screws at 10,2,4,8 o'clock
take off rubber trim ring from grille
mark and drill out the circumference ring of the grille
notch the back of the rubber trim ring at these locations
reinstall rubber trim ring
mount on top of passive, align holes, pull back front of rubber trim and reinsert hold down screws.
June 3, 2008 - 'we will no longer be needing your services'.
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