RE: JR Receiver Futaba Servos???
The only time shift matters is between the transmitter and reciever. Once the signal is decoded they all work the same way.
So the answer to the question is yes you can use futaba servos w/ JR reciever and vice versa. You can also use the Futaba gyros.
As stated you will have to shave the futaba index tab off with a razor blade but thats about all. Most servos with the exception of some very old ones (airtronics specifically) will work with any reciever.