Orma,
I just had a "brain fart" on your turbo cooling issues. While an insulating
sheild of some sort will protect the imediate area, there is still the issue of
trapped heat in the rest of the cowling. A better solution IMHO is a simple
"trap door"
that is held closed by the flow of cooling air when the engine is running, but
falls open when the engine is shut down. I saw some on a RV many moons ago,
they were simple pannels that had a section of piano hinge at the forward end.
The owner said before this his engine (fuel Inj lyc) was a bear to start when
the engine was warm/hot. Even with the "recomended Starting procedures" after
putting in the doors it was a whole lot easier to start when warm/hot.
Bill Higdon