> The fiberfax was not trimmed, just squeezed behind the stainless.
>
> Yes there is slight dimpling, so what? If there is a fire, the
> jig will be up long before that connection gets hot enough to fail,
> why add the extra weight?

The reason to not have fiberfrax under the engine mount has nothing
to do with fire protection. Instead, it is to avoid any crushable
material that is being compressed by the bolt. The bolt can only
do its job properly when it remains under sufficient tension.
The relaxation of the fiberfrax can reduce the preload on the
bolt, allowing motion in the joint. The motion then allows surface
wear and fatigue. Unchecked, the engine eventually departs the
airframe with unpleasant results for everyone.

There aren't many bolts in a Lancair, but the ones that are
there are pretty important.
For a good education on bolted joints, try Carroll Smith's
"Nuts, Bolts, and Fasteners".
http://www.amazon.com/Fasteners-Plumbing-Handbook-Motorbooks-Workshop/dp/0879384069
ISBN: 0-87938-406-9
It's not a dry technical manual. It's written by an opinionated
outspoken race car fabricator, and chock full of useful and
interesting information. Read it cover to cover and you'll be a
better airplane builder when you're done.