Brian and Ed,
Thanks so much for taking the time to check that for me. That info is hugely helpful.
My reels are about 4.5" which will wastefully fit a 2500 tank and now I see will not fit a 1500 without the help of a mallet. I have a tank that will take up to five of these old reels or two old style 4x5 reels and would love to find one that would take a couple of 35's or one old style 4x5. Looks like I am out of luck unless I find something in a junk bin.