Sanjay--Thanks for the 6.5"! It arrived and it fits the same mounting collar as my 10" lens, so I was able to mount it, and it does focus and covers the full lantern slide format. For projection at home, I think this will be my main lens, since I don't have much room to move the projector back from the screen. It's got some fungus, but the external surfaces cleaned up easily with some Kodak lens cleaner, so I'm hoping the same will work on the internal surfaces when I take it apart.
I'm not sure why it wouldn't focus on your projector. Check these things--
--The lens should be mounted with the lettering toward the screen.
--The focus track can be extended or shortened by loosening the two knobs under the focusing carriage (you may need to move the front standard backward or forward to make room for adjustment. If you need to move the front standard out farther, just pull out the track, and to make it shorter, you can push it in.
--If you've got the focus track already at the minimum range and need to push the lens back even more, remove the lens mounting collar by loosening the knob on top of the front standard, and then there is a set screw on the bottom of the collar that you can loosen to change lenses or move the lens forward or backward in the mount. One turn or even less should be enough to loosen the screw.