My Imperial has always had a bit of a leaky power steering system. I replaced a hose, but it still leaks. Now, after I’ve driven it a bit, it doesn’t have much power at idle (like when parking) and makes noise. The reservoir is low-ish but not low. It’s over the vanes in the pump and just needs a little topping off. What are the symptoms of steering boxes going bad? Just the pump? Aren’t there two types and one can (should?) be converted to the other?