Not too sure if it matters with a trike(landing gear), but how do you go about ballancing out the center of gravity with all your electronics that you end up putting into the fuselage? Does it usually end up with modification city, or do most models leave room for movement and different placement options?

landing gear doesn't matter, since the CG is much more important in the air. depends on the type of plane. trainers generally don't offer much to easily move around, but they also don't need much adjustment if you use the recommended engine size.

to get the cg right on my stinger 1.20, i had to move the firewall back 1.5 inches, move the servos to the rear, and install a hatch in the back for the battery. (pretty extensive mods)

and finally, you ALWAYS want to move functional weight before adding weight. if you can shift a battery pack, go for it, at least before adding lead. or use a larger pack/better servos/etc... if you have to add weight, add it as far out as possible to the needed end. (weight on the end of the vertical stab or a heavier spinner)

Often, the LAST thing I do is to install the radio.

I will move the servos and battery and reciever and switch foward or aft to balance the plane. Lead is very rarely needed.

I agree with kingwoodbarney, put the radio in last no matter what the instructions say. This is an especially good policy is you are using an engine larger than specified, which a lot of us do.

I normally install everything except the battery, rudder and elevator servos. Then I put the battery near the middle of the plane so I have some movement leeway later on. Then I rubber band in place the rudder and elevator servos and check the CG. If I am nose heavy, I move 1 servo to the rear. Still nose heavy, I move the other servo. Then I move the battery.

Installing servos in the rear fuselage is fairly easy. I normally just cut a hole, screw them in, remove the screws and treat the holes with thin CA and re-install the servo and hook up the pushrod. Normally, I can use a short piece of 2-56 or 4-40 rod for the pushrod. For rudder in the rear, I have been mounting on to- the fuselage and using short pull-pull lines to the rudder. You can also install the rudder servo on the bottom for pull-pull. Bottom would be better for an upright engine.

The most work I have had to do for rear mounted servos is to add in a little ply in one of the lightening holes for the mount. Usually the fuselage sides are 1/8 lite ply so I cut a small piece and back it on the inside with some 1/32 ply. You will need some servo extension leads.

Sure beats adding weight.

Nice. What is the easiest method of checking the CG once the build is complete and the engine is in? Kind of a general reference for all types of planes.

CG point should be shown in the instructions or described usually as a point of measure back from the leading edge of the wing at the root(right up against the fuselage. for example you may see that the book says the cg is 4.5", that usually means you measure from the leading edge right up against the fuselage back 4.5". That is the recommended CG, yours will be listed somewhere in the manual. I mark that point with a piece of tape or a sharpie on each side of the fuse and then lift the plane up touching only those points. From there you just move things around until the plane balances on those points. Usually on a trainer the CG is right on the main wingspar.

Thanks for the input Ned.