Question re: burner tubes

Ken C.

Hello,
I'm a fairly experienced plumber, but now that heating season is picking up, I'm being thrown into heating service calls despite the fact I have little heating experience (I can get some help via cell phone - when it works).
I'm reading as much as I can, but have been told that the best way to learn is to get hands-on experience, so I'm learning as I go.
So I cleaned my first hot water boilers today. The first went okay, the second one kinda threw me. I believe the name on the jacket was Crown (although a tag said Dunkirk).
Anyway, after I cleaned the boiler's flue passages, I went to remove the burner tubes (they were cast iron). I got the front of the burners free, but could not get the back of the burners to lift out. I tried removing the side jacket, but that provided no access to the burners. Finally, I shined a light inside the boiler and found that all three burners were tied to the chassis with baling wire!
My questions are: Is it common for burner tubes to be secured to the boiler frame with wire ties? Is this done for shipping? Should the original installer have removed the securing wires? Was it even necessary for me to remove the burners at all? On many boilers, the burners usually just lift out, especially the newer tubular steel ones.
Nothing like learning via "trial by fire."
Ken C.