The filler neck enters at the top.
We don't have a HD close by until we get near Seaside, so might check at that time for the water meter.
After we come off blocks tomorrow, will try to fill some more.
Tinmania, you are correct.. We have a 12 gal Suburban. Guess that makes sense it's only holding 56 gallons instead of the projected 68.
Who knows, they might even include the water lines in that number.
Trackrig, I don't believe there are 2 water tanks. There is only one fillneck, and one input and output from the water tank. Would have to take down the underbelly to verify.
Thanks all. Appreciate the input.
Safe travels
Richard