Ok... this has gotten out of hand and I apologize for it. I think I agree with "Friendly Bob" that we are picking knits. I'm NOT saying that closer is necessarily BETTER in a structural sense (we're not talking about enough weight to cause significant flexing in a solid 1-5/8" shaft anyway).
I'm saying that if your bearings are good enough, you can have a less bulky and lighter mount by putting the bearings closer together. If transportability is not foremost in your desires (as they are with mine), then a wider bearing spacing would be just fine.
Thanks for bearing with me (so to speak). :-)
Andy Steere dmislas@clark.umsystem.edu