I'm still trying to find a copy of the 337 for inverting a Schweizer towhook on a Pawnee. It seems I need a N number for the FAA to track down a copy of the 337. The 1996 article attached says a 337 was granted by the FAA, and I suspect this was for the Pawnees operating at Turf. Does anyone know the N numbers of the Pawnees operating in the 90s at Turf?

https://www.dropbox.com/s/bsp9r0oj2n...hooks.doc?dl=0