I also only remove the battery, but it does suck getting gas hoses off with only battery removed. Removing side panel isnt too hard except for top hood hinge.
Those hoses were on there for 10 years. They got comfortable and took up knitting.
I was able to pull one off with two hands. The other required a tool to move it:
wirecutter.jpg (29.42 KiB) Viewed 492 times
Didn't cut the house, just used those cutters to pry it up a bit. That really helped.
There is nothing wrong with the plenum tank or regulator. The gas valve leaks when closed. I decided to replace the whole unit instead of trying to find a valve and gasket. The tank has a very small amount of surface rust along the seam. It was leak tested last year.
I use the Milwaukee cordless heat gun and some WD40 to get the hoses off, especially during winter time. I've seen solenoids not tightened down enough into the cork gasket hence some leaks, some you could smell easily.