Tank Dimensions?

[Cracker]

Can anyone provide the exact dimensions of the waste tank on a 2000, 30' Excella? With that in mind - my real goal is to be able to tell, for sure, just how full my waste tank is by measuring the liquid depth thru an open toilet. I've never been able to fully trust the electronics (---has anyone???) and I don't like worrying about an overflow! As an example, I've already winterized the trailer and drained all of the tanks - but my waste tank reads 2/3 full and the liquid measure thru the toilet shows 2 inches deep. It should only have 8 ozs of deodorant, one gallon of water, and about a half-gallon of anti-freeze in it. I thoroughly rinsed the tank when I checked out of the campground last weekend - knowing that I was going to winterize the trailer this week. That said, the 2-inch direct measurement seems a bit odd? I've tried cleaners, ice cubes, and several other tricks to clean the tank sensors - but to no avail. The direct measurement procedure, however messy and distasteful, would provide a reliable reading! Several calculations, with reference to the current 2-inch liquid depth, suggests that the tank may have a slightly sloping bottom and be somewhat deeper just under the toilet. It's that - or the tank discharge is partially damned up.

[Cracker]

I know that waste tanks aren't an exciting subject - but I'm surprised that nobody seems to have the dimensions??? Maybe my use of "exact" was asking too much. I'd be real happy with an approximation.