Scott,
if you are interested i may be able to help.
i made a file to cut the shape. fits like a glove.
i got sketched at a first too about the plastic, but they have been running this style for over 20 years. i cant remember one story of the housing busting leaving the clutch inop. so i decided i would just imitate chrysler. the instructions i got with the hydros from Valair said that the waranty is void if the mount isnt appropriately snug. i it does seem very sturdy now that i have it in there.