Thanks all for responses! Here is my plan and a couple of take aways from the responses. I would appreciate any contrary opinions or additional suggestions.
A special thanks to Billy for providing photos and location of the inspection hatch for the 55 fuel tank, this takes half the worry out of it for me.
Tomorrow I plan to open the inspection hatch and see what I can see. I would be surprised if it is clean based on what I have seen in the Racors the last two years. So I am wagering that I will need a professional tank cleaner.
There is a local vendor who will suck out all the fuel, clean the tank completely, polish the fuel while out of the tank, then put it back in. So I will use him unless my inspection suggests it is not needed.
Once clean, I will change out the Racor so I have a baseline for subsequent filter changes. Then, plan to use the Grotomar additive religiously. It has several quality endorsements from sailors, and based on the fact it is very difficult to find, it must be good.
In my unofficial research, the StarBrite treatment received a good number of positive mentions, and importantly, I see it often in the Med chandleries.
Once all clean and full, I plan on a three year visual tank inspection interval.
I will provide an update when the work is done.
Again, thanks to the group for all responses and suggestions.
John W. Clanton
S/V Devereux, A55, No.65
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