We have a 31DSLB and have the same 2 tank set-up as you do. It has two 24G tanks. One servicing just the kitchen sink and the other services the bathroom shower and sink. Ours can not be equalized without modifications.
As for the gauges, we must be 1 of the few lucky ones as every trailer we have ever owned worked right up unitl the day we traded in. Knock on wood now.....
2012 White Hawk 31DSLB
2013 F150 FX4, 6.2L, 3.73ELD w/ Max Tow Pkg