Trip Mitchell

Guys, I have this chirp in my dash and it is about to drive me crazy! 2016 GMC 2500 6.6. I have two battery trays, one on passenger and the other on drivers side. I took a general look into this under my hood and was able to barely get to a few of the battery tray bolts, but if there are more they are not accessible without removing a lot of batteries, hoses and equipment. Before I do that, can you all confirm a few things... 1. Which battery tray was it or are the referenced above only for single battery trucks? Did you have to remove everything to get to this bolt? 2. Please confirm this sound is like a consistent chirp in the dash every time you hit the slightest bump and I cannot pinpoint location as every time I lean my head down it sounds like it is coming from a different direction... it is also very loud and it is really hard to think it is coming from the engine bay... same thing?