looks good.
I also thought about your first method....Connect all the parts together before connecting them to the chassis.
in theory it works, but in reality it is very, very difficult.
I prefer to close the part/ring and then thread it on the chassis as in the instructions i wrote, but if you were able to connect the parts as in your second method, then well done.
A small note ....
When you reach the air intake, try to stick to instructions, because the air intake are very long compared to other models.
But how do we say....No matter how we get from one city to another, the main thing is to get there safely, safe and sound.
keep on the good working.
YOAV