That to my knowledge is the only way. I just did this a few months ago. Due the the irregular shape of the tank up under the side body panel, it just can't be squeezed out. It is good however to do lots a simple maintenance while the engine is out and look for other signs of rust. My tank rusted just under the half support under the tank. There was a rubber strip glued to the tank and water had been captured under that spot. What was first a pin hole changed to a thumb hole when I applied pressure to the rusted point. There are several options on replacement tanks that range from the hundreds of dollars to the thousands, so understand your current and future use and budget. Remeber to change the hoses while you are there, it will save you time and grief in the long run.
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