I loved seeing this thread until I came to the engine block failure.
I just purchased a new fuel tank for my '87 18SF from RDS. Because of hose particulate matter in my pre-filter, I ran new fuel fill and vent lines from a new location at the rear to the old tank only to discover I also needed to replace the 31 yr. old fuel tank because of corrosion on the fill and vent necks.. That's coming up as soon as I get enough time free to run and fish the remaining 35 gallons out of the old tank. It goes through 3 filters before getting to my motor. A see-through glass pre-filter, a Racor water-separating filter with viewing bowl, and a small 10 micron cartridge filter I added on the motor.
When I mounted the 90 Etec this summer, we tested the transom and it was completely dry. Yay!
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Common Sense is learning from your mistakes. Wisdom is learning from the other guy's mistakes.
Fr. Frank says:
Jesus liked fishing, too. He even walked on water to get to the boat!
Currently without a SeaCraft 
(2) Pompano 12' fishing kayaks
'73 Cobia 18' prototype "Casting Skiff", 70hp Mercury