I have the oportunity to relocate the fresh water in our 1974 H25 Mk 1 and want to stuff a pair of flexible tanks under the main-cabin berths. The available space is about 48" x 16". (I have no idea how many gallons this is; the shape is irregular.)Does anyone know of decent flexible tanks that come in anything close to this size? I have scoured all the catalogues and have come up with someone's in 41" x 28", but I am concerned about stuffing too much tank into too small a space. Seems to me the idea would be to get as close a size as possible and not attempt to pour water into folded-over corners and crinkled seams, etc.I'm hoping someone has had better luck finding tanks other than the ones listed in all the standard catalogues, and for less money than I am looking at. Something under $100 for such a limited size would be ideal. Much over that starts to make bottled-water jugs with garden-hose siphons look practical!Thanks!