I highly recommend reaming out or re-tapping the bolt holes in the frame for the front and rear stabilizers (4 holes) and possibly the four bolt holes for the upright. These are often poorly tapped at the factory and can result in breaking a bolt if they are forced.
Pay particular attention to the orientation of the upper body arms and the upright. I have seen these frequently assembled backwards requiring partial disassembly and reinstallation
I do not recommend using a power driver or screw gun to assemble or attach the plastic parts. It is easy to crack or break the plastic.