I have an Omega B600 enlarger. I'd like a medium format negative carrier. I understand that the B600 and C700 have a lot of mutually compatible accessories, but I also know that the B600 can't do anything larger than 6x6. So I found this on my local Craigslist. Does the MF negative carrier pictured look like it will fit the B600? Or is it possibly 6x7 and only workable with the C700? http://pittsburgh.craigslist.org/pho/2611533464.html I don't have a lot of experience (yet) with enlargers and accessories. Thanks.