Cyclic Hardover:
Well you can buy plugs, pumps, change nitro and waste quite a bit of money and your problem will not be solved until you lower the tank. Can you cut out the mounting bulkhead and rest it on the bottom? I run three planes like this. I cut out that bulkhead and made a new design to hold it securely on the bottom of the fuselage in the nose. All these planes run perfectly. Other than that, can't help you.