Thanks for all the comments!
Last night, I took some time to take some front brake reach measurements. I measured the distance (in as straight a line as I could get) from the center of the brake mount directly to the centerline of the quick release skewer (with wheel removed). The distance measured about 367-ish mm and multiple tries put me in approximately the same area. Since alot of this was with the eyeball, I'd guess that a measurement estimate of 370mm would be conservative. Do I need to measure the rear too?
Using the 370mm conservative estimate and Dia-Compe 750 centerpulls (75mm reach), the calculated smallest wheel size comes to 590mm. Just 3mm short radially. If I trust my eyeball and measuring skills, the 367mm measurement gives me a smallest wheel of 584mm. I trust the 370mm estimate more since I never measured anything less that 367mm and I figure it could compensate for manufacturing tolerances as well. UGH!!!!!! This still doesn't tell me for sure, if this will work or not.
To just "Do it!" would be a $400 experiment, so I'm not willing (yet) to go that route. So again, any info from people that actually have this set-up would be reassuring. Or if anybody is going on Chuck Schmidt's ride this weekend and has a Dia-Compe 750 and 650B that I can try on, that would be even better.
Doland