I built something near that in the mid-late 60s. Basically a BTR without a canopy, inverted Johnson BB36, half pan, and large tank. Met it's demise at the '63 NATS, Los Alamitos. The down line broke during practice, three large loops, then pancake. Lost everything. The pan with what was left of the engine skittered down the ramp about 100 yds and hit the leg of my brother walking toward the hangar with his back to the circle. He never saw it coming. Weird how with all the radial directions the wreckage could travel, it had to pick that one and my bro on top of it!