OK, prolly a really naive question (new owner). So I’m wanting to set up a tarp (boom tent) to protect part of my newly purchased 1987 Catalina 30 Mk II. The boom doesn’t look quite level, aft end droops a bit. So I set about leveling the boom so I can set up the tent evenly. I centered the boom on the traveler, eased the main sheet and the boom vang, and went to winch the topping lift line to raise the aft end of the boom to level. It’s fighting me. Am I missing something?