Richard, a thank you from me also for your list of variations.....between you, Carlton and several others here on net54, all of you have helped my variation collection flourish.
I have not openly sold a BB MB card in years, as before I started this set myself, Carlton was the recipient of my BB MB cards. However, I have sold some of the MB FB cards over the years...my recollection is that they have basically sold for twice what the same regular issue card would have sold for. The cards I sold were all ungraded, so there were no pops to worry about.
Here are some of the closed sales on ebay for 67 MB football:
http://www.ebay.com/sch/i.html?_saca...H_Sold=1&rt=nc
For 68 MB baseball:
http://www.ebay.com/sch/i.html?_odkw...adley&_sacat=0