Fujinon 210mm f/5.6 - Question about the old version

I was looking into the old version of this lens (lettering on front rather than side of the front element) when I noticed something. The rear elements on these lenses are not all the same in the various listings (only looking at the old version). Some of them are rather short narrow tubes kind of like a bottle cap. Some of them have rear elements more like the new version where the element flares out in the middle. And there seemingly is a 3rd version that looks like the first but is a bit wider and longer and the rear glass does not go to the full width of the element instead being held in by a tapered retaining ring.

Does anyone know the difference?

Are these all correct, or could some of them be the wrong rear element on the lens (seems unlikely). I'm looking for a lens that'll cover 8x10 with as good a quality as these Fuji lenses can muster at the coverage and now I don't know what to look for. These are all older lenses with the internal identification markings. I've not tried to correlate serial numbers yet to see if there is some kind of pattern.

I have one of these lenses, the W 210/5.6, inside lettering, version. I took a brief look through ebay listings for Fuji 210/5.6 lenses.

- The shorter, narrow tube lenses are labeled as Fujinon-L 210/5.6, which is a Tessar 4/3 design, not a plasmat 6/4 like the W. The L will be smaller and lighter but have less coverage. Occasionally a seller may mistitle L as W, but look at what it says on the front ring.

- For the wasp-waisted W lenses, I'm not sure exactly what difference you're seeing (links or pictures would help), but I know there are versions of this in both Seiko #1 and Copal #1 shutters. The lenses in Seiko shutter may be named Fujinon-W-S. The Seiko shutter has a different mount thread (this is the one I have, the only reason I know this minutia). Thus the lens cells may be different sizes, but I have no evidence that the optics are different. The Seiko requires a slightly larger lensboard hole, so if you get that one, be sure to get the retaining ring and better yet get it already on a lensboard. If you don't want to deal with that, get the Copal #1 shutter version.