At this stage, the T-Rex 250 is about completed. Mount the ESC and clean up all the wires to ensure nothing gets caught up in rotating parts. The manual also suggests installing the receiver as far away from ESC as possible, which may not be needed with the modern 2.4Ghz receivers.

For those who has a couple of T-Rex kits under their belt, this build will feel right at home. The kit can literally be build in an evening or two, provided you didn't have to search for lost screws in thick carpet like I did. Did I mention the parts and screws are really tiny? I didn't realize I need reading glasses until I started building this heli. Luckily Align has provided a bag of spare screws/washers in the kit, just like they do with all their other kits.