99 times out of 100, if it doesn't specifically
state that you can
do it, then it's not legal.
I spent about 1/2 an hour searching as well, and couldn't find anything specific to the balance shaft.
^^^Other than balancing the rotating assembly is not allowed in ST.
In fact, "balance shaft" doesn't even show up in a search in the PDF.
Isn't the balance shaft that you're deleting internal to the engine?
IOW, it's not external like the crank damper or a pulley, so 14.10 doesn't apply at all.
I guess I should peruse the Duratec forum and read up on the balance shaft delete a bit more.
I suppose at our regional level it's not a big deal, but Divisionals or Nationals could get a bit iffy.
Then again...maybe you shouldn't have mentioned it at all. LOL!