Fireball-- I removed the tank from my 390 and I did not have to remove the fridge/step wall. Remove all stringers and plywood and the supports around the large hatch, the tank can slide forward and as it slides forward lift the front of tank and pivot out from under the wall, its very tight and you'll be bitchin but it does come out. I no longer have the 390 but I owned my 1989 for ten years before moving up to 420. I had the factory installed aluminum tank that started leaking the first year I owned the boat. I removed tank cleaned all the pinholes on the bottom, sealed them with epoxy and "urea" (truck bed liner). This held up the next 9 years until the boat was totaled by ins co.