18 Fuel Tank question

[Beaver]

I'm finally getting around to pulling my fuel tank but have a couple questions...

1) I have drained all the fuel but have read where guys recommend adding soap and water to the tank and draining prior to pulling and disposal. Is this an important step?

2) Any suggestions on disposal of the old tank?

3) I read that I should attach neoprene to the bottom to help it from sliding around. It s a Moeller poly tank, should I do this?

There is probably a bunch of questions I don't even know to ask so any feedback is greatly appreciated.

Thanks.

Rob