I would highly recommend Boulder Offroad for the items you mentioned. Located in Lafayette, CO
They fabíd up and installed a new larger front sway bar and sway bar mount on my rig, first with end links and now with disconnects, greatly improved overall handling and got rid of my bump steer and front end slop by getting rid of the undersized sway bar that consistently wore and wallowed out the bushings. They do great custom fab work and can most likely take care of the welding on your tank.
Shoot them an email and you can try calling, Don will eventually get back to you as heís often in the shop working on rigs and not manning the phone.