Here are some pictures of a radio installation that might be a little more appropriate for your glow model (standard servos are used since this is a 40 size model). You can see how I went about planning it and then changing things as it went together. I needed to make sure the area behind the wing LE former was able to be cleared so I could remove the fuel tank if needed. This particular model doesn't have a front tank bay hatch like the SP.

I should mention that here the servos' are installed in a staggered fashion because the elevators are independent (not joined) and operated by a forked pushrod from the single rearward servo. In front of that servo is the rudder servo which is centered on the fuse center-line and used with a Pull-Pull wire setup rather than a pushrod. In your case, using two pushrods, you can simply install the servos for the elevator and rudder side by each in the back with the throttle servo just forward of them as described in the post above. Very similar to what I did on the SP but it might help to cut a servo tray on which you can mount the receiver -especially if it is a small modern 2.4 GHz type Rx which is hard to pack in foam.

I mount my receivers by using double sided foam tape on a little lite-ply board which in turn is velcro'd to the radio tray or fuse side. This helps to insulate them from vibration. One can also use a velcro strap with the Rx backed by a piece of foam rubber but they have been known to slip on occasion from under the strap.

David.