Here is a plane made with two "sticks" combined, as Bill suggested. That is a trainer fuse in the middle. Stop the booms on the wing, instead of putting engines on it. Make sure you have room for getting your hand into the second engine safely.
Just a thought, lengthen the center fuse, to the rear, and mount a second firewall. The trainer has a front firewall..........mmm...let's see, I left the front firewall in this..........lengthen the trainer fuse to the rear.........mmmmmmmm. have two ST 40's laying around....four?......mmmm
Check you later....uh got to go....uh look at something!!
Twinman