I disagree, Frank. It is better to do everything at once, it’s not exactly hard work. Do it right or just drain a tank and see if it helps, I’ve done everything individually and would adress everything at once next time.
I would never remove the tanks if they are still tight. Just get the rust out, with already stale fuel 
The hand pump might be practical, or a siphoning hose with those little pumps to start by hand. Or you accept the taste, what you need to know is that the pump pickup works good for draning.
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