personally, i install the electronics before i build the Trex

ie, i install the servos before the upperframe goes into the bottomframe so i can tear the bearing block off and route the wires inside the frame.

i use a swashplate level tool instead of measuring the linkages. i build all the head linkages with according to a pitch gauge rather than measuring the links.

i finish the tail before i attach it to the heli. without the 401 (will be the same as non avcs mode), i setup the servo and its mechanical center and then plug in the 401 to adjust the limit pot.

btw, if you want to make ball links easy, use an exacto knife stick the tip into the bottom, give it a good twist, and then the rods will thread effortlessly.

you shouldn't need instructions to build an SE...

btw, the stock dampers aren't so durable. i would upgrade them with the aftermarket or silicon fuel tubing as they will probably only last 10 flights if even that. Pay VERY close attention to the belt tension on a new trex align belts need kind of a break in or they WILL snap. They stretch in the beginning and you need to run it a little tighter than normal until it does then you adjust it until it is good. you'll know if you snap one. buy the HDX/3DX450 aftermarket clone belts which are made by GATES or MS.

id run the heli without blades for a good 5 minutes before flying it just to stretch the belt and make sure it's tensioned correctly. the belt should almost be able to touch the other side if you press it with a tip of a screwdriver 1.5cm away from the pulley.

use the smaller pinion on the 430XL. i would cut a flatspot in the shaft of the motor so the pinion doesnt slip or fly off.