Bob and everyone,
I have done just what Doc Johnson suggested.  I used enough of the
soundproofing material to do the firewall and under the front floorboards.
This was done with the one inch hard back material.  I may use the 1/4" hard
back material to do the right and left fuselage outboard of the pilot's and
co-pilot's feet, behind the sidewall.  That would help keep those feet warm
at high altitudes.
I contacted the company, Soundcoat, about buying more of the 1/4" stuff but
the set up was prohibitively expensive.  The remainder of the factory kit
will go unused.  The interior specialist, Jim Griffin, plans to insulate all
of his interior linings with something to help with sound and heat.
Walter Dodson  IV-P  87%?!+/-
ps: My guess is the soundproofing kit weighs about 40 lbs.