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Ancient though it may be, this mold nevertheless includes a hull which looks very plausible - for (at least) SOMETHING or other:
At 13.6 LWL, this equates to a Ranger in 1/644 scale - however, based on the more important BEAM (max.) of 1.75", it could be lengthened to produce a Ranger in 1/549 scale. That would provide a third conversion candidate, squarely between the 490-scale Revell Yorktown- and 600-scale Aurora Enterprise options - and closer than either to your 570-scale Revell North Carolina, and Lindberg Riley DE. Yum! (And likewise for the rest of your historical lineup of 1/525 Lindberg Essex, 1/535 Revell Missouri, and 540-scale Revell Midways and later, angled-deck Essexes.)
You would have to add a whopping 2.37" to the length, for a 549-scale Ranger, but note the center section of this hull does comprise a slab-sided area where this would be easy to do. Alternatively, it would also be relatively easy to make a true, 600-scale Ranger - by adding exactly 1.0" in length, but also reducing the beam by 0.15".
In any case, it's an enticing use for this reputedly innaccurate Savannah mold - correcting which might well require just as much effort as making it into Ranger(!) - particularly if you want to spare your Aurora Enterprise mold, and have far less interest in building Savannah, in the first place, than your obsession with (a 550-ish scale) Ranger!