ORIGINAL: id_ram
Thanks for the detailed instructions.
But isn't there a way you can make it out of sheet balsa or something?
You certainly can make it out of sheet balsa. You can also make it out of a block of balsa.
The block is the easiest.
Fit the block to the opening.
Draw the outline on it.
Remove the wood that's outside the outline.
Hollow out the insides for the engine.
Figure out how you wish to attach it to the airplane so you can take it off and put it back on.
Cut out the openings the engine needs.
Fuel proof it.