That could be Hugh, when I said "always said", I meant since I first looked two days ago. I guess that really isn't "always".
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2017 Escape 5.0 TA
2015 Ford F150 Lariat 3.5L EcoBoost
2009 Escape 19 (previous)
“Most folks are about as happy as they make up their minds to be.” — Abraham Lincoln
Just as I was typing that last post, I got an email from the seller crediting me $7.00 plus GST. Not sure why, but I'll take it.
$7.35 will buy me a large bottle of craft beer.
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2017 Escape 5.0 TA
2015 Ford F150 Lariat 3.5L EcoBoost
2009 Escape 19 (previous)
“Most folks are about as happy as they make up their minds to be.” — Abraham Lincoln
So I guess out of luck for the grey and fresh tanks of you go for the spray foam insulation?
Right - if you are checking visually as an alternative to electronics, you need to be able to see it. For the black tank you have the toilet as a port to the inside, but there isn't an equivalent for the other tanks... so if you can't see the outside (due to insulation) then you can't see the level.