One thing I also read that Electron 6's negative shift Rx works with Futaba. JR's is working +ive shift. Many senior flyers would provide you great advices including moderators. I don't think I've ever seen marking of positive shift or negative shift, try google the image of Electron 6 and of course it's been replaced by Neutron 6 now.
http://www.hitecrcd.com/products/rec...eutron-6s.html
Best of Luck
Mody