Re: jb weld?
To mount the tank permanently, simply use Urethane Windshield Adhesive. It comes in a tube like caulk, you use a caulk gun to put it on. When it dries it's permanent. I've done two bikes this way and never had a problem. I don't even use the brackets. Make sure the two areas to be bonded are clean. I do leave the studs on to help hold cables but they can be cut off.