Before I got the idea to locate the batteries forward of the rudder peddles, I had already filled the exhaust ramps with foam and then covered that with of 4 layers of carbon on the outside. Later I ground out the ramps themselves from the inside and of course the foam I had installed a few months earlier. No wonder this project has take 9 years so far! I had originally built with the idea of using the V8 and the switch to the turbine caused a lot of remodeling. Pictures of the rudder/battery setup are with the reply to Joe's email.

 

Regards. Dave.