RE: Futaba servos and JR Tx / Rx
yup, I have a lot of old futaba servos and am using them with my JR 2.4 . They work fine.
I found that a small pair of side cutters work on removing the little tabs on the futaba plugins. My pair have a jaw depth of about 1/4 in. You still might have to shave off a little with a no. 11 blade and put on champers ( little 45 degree corners ) on the one side to work with JR RX units.
If you look at the JR servo plugs you will see what I mean.