Hey - I have a thought - completely untested...

I went to that B-Quiet website and couldn't help but think, except
for the alumized flavors, that the stuff looked a lot like rolled
roofing membrane - Ice & Water Shield, Bituthene, etc. - these are
rubberized asphalt / HPDE, self-adhesive films that I'd bet would
be even less expensive /sq.ft. than B-Quiet... If someone can get
their hands on some construction leftovers for comparison, it
might be worth investigating. Just my completely un-researched and
un-expert observations - proceed at your own risk please.

Doug Fitz-Randolph
Freeport, ME
'90 Syncro