Bung welded in, tank mounted, toolbox remounted. Went with tank forward. If I remove the bed the aux tank doesn't need to be screwed around with.
My filler neck isn't the size it was supposed to be so it's not plumbed in. Ford and Dodge are supposed to be 1.5", GM is supposed to be 2". I'm 2". Also found that my filler neck is toting from the outside. Has a pin hole, that'll need replacing. That, along with a working spare tire winch, are on the J&J list.