Don't forget the silicone tube.

Epoxy one side first.  Do not epoxy the other end until you mount the tail boom.

Check for smooth movement of the assembly.  Resize the ball joints as necessary.

Solder the ground wire.

Insert the tail boom into part 426 (body boom support block)  Place the belt around the gear.  Pull the tail boom back until the belt is tight.  Use a sharp object and mark the tail boom through the block of where you will be drilling the hole for the screw.  Make sure the main body is leveled and the tail's fin is 90° vertical when marking the hole.

Then remove the tail boom and block.

OPTIONAL:

To be able to tighten the tail boom belt just a little more,  just in case you feel it's not tight enough, I lengthened the hole towards the rear of the tail boom block.  This way just pull on the tail boom to tighten.  The screw and nut for the ground wire will just have to be tight enough but not too tight.

Tie a string to the belt from the front end.  Pull the belt from the rear.

Insert the screw from the inside.

Put one end of the ground wire first, washer then nut.

Pull the belt out with the string.

When sliding in the tail boom keep in mind the supports.  You can mount them either from the outside or inside. 

Mount the tail boom with the support block.   Make sure the belt is tight.

Notice the loose screw for part 472 that holds the tail belt roller.  Tighten this after.

Secure the other end of the ground wire as shown.

Adjust part 391 (gyro plate mount) either forward or backward so that the servo horn is vertical and the long end of the bellcrank on the tail rotor is 90° perpendicular to the tail boom.   When you have this set, tighten the mount.  At this point the ball joint shouldn't have been glued down yet. Use epoxy

Don't forget to tighten the screws for part 472 from drawing #7b.  This holds the tail belt roller.

NOTE:  Read this forum thread.

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