Upgrade to a 722 will keep all the wiring in the house the same, dish will be exchanged for bigger one to get you HD. Doing this will also help you with your aiming problem since new dish would be aimed when installed. Second tv could remain sd since single sent to it would be sd. If you wanted both tv's to be HD, interior wiring may need to be changed somewhat. Upgrade fee depends on what you upgrade to, and your history. You should pm a DIRT member to answer that question.