I have a Great Planes Matt Chapman Cap580 (the 55" wingspan) When the manual says to install the engine mount. It says use the blind nuts through the back of the fuselage. How do they fit?? And are the blind nuts the ones in which you have to stick into the wood?
Thanks!

This is a blind nut.

you drill a hole through the firewall big enough for the shank of the nut to go through and is pressed in from the back side/inside of the firewall. the bolt goes through the engine mount into the bilind nut. it hold by nut digging into the wood

Great! That's what I thought. Thanks!