Has anyone tried this?

http://escomposites.com/soft_mount.htm

I have not seen it running but Ed has something similar on his Alien
with the ZDZ RE and says it works well.

Cheap, light, simple, no large excursions to break your header.

Each wellnut is a different distance from the crankshaft axis to prevent
the engine from getting in sympathy with the airframe at any one
rpm.