Wanted to mention this bit about the ammo belts. I did this the way the tut said but it didn't work out very well. Parts were too close together and I couldn't get the curve on the second one to match the first.
So I started again this time building each one a stage at a time.
This worked a lot better.
Each one of these is an instance - the tutorial sets everything back at the origin before instancing, then re-positioning back at the proper place. I found (using modo 302) that I didn't need to do this, instancing worked fine without moving the original item to the origin.
As I was doing the last one I thought, can I instance an instance? Well it seems you can. I instanced that last section from the last instance of the previous.