This pic taken at Santa Barbara in Sept' 1974 and nearby was N156WC the Conroy Dart C-117 conversionDidn't Conroy propose a single-engined turboprop conversion of the O-2/Model 337 with a Garrett TPE331 in the nose and with the back end reconfigured to side-hinged clamshell doors like some C-119s?
This pic taken at Santa Barbara in Sept' 1974 and nearby was N156WC the Conroy Dart C-117 conversion
I only normally link to the Flickr images so the watermarks are highlighted and enlarged in comparison to normal
AFAIK, Conroy used the name "Tri-Turbo-Three".