After more than a year of deliberation, I am putting it together. I've read a lot of useful posts on this web site and have decided the following for my setup.
OS 91 FS with pump, 14X6 APC
Hitec High torque rudder servo with pull-pull, Futaba Micro for the throttle,
individual Hitec high torques for ailerons and two Fut BB standard at the rear for elevators.
600 mah 5 cell pack.
Radio: Fut 6XAS PCM
This is the first time I am getting the servos at the rear and would like to know if I need some sort of filter to avoid RF interference. The distance from the servos to the RX is 28" to 30".
Thanks.

I do not think you will need anything special for this setup. I would simply do a thorough range check with the engine running and not running before flying. If the range check is good then fly. I have extensions this long, or longer, in my 29% Edge with a Brison 3.2 and have not had a problem. My extensions do not have a plug and are put together using solder connections...

Thanks Galen,
I shall test it with the engine running.