I am in the process of restoring a 1949 Lincoln with the big engine (F8).  The rear OD seal where the drive shaft enters is in need of replacement.  I have been unable to find one that fits.  One of the popular vendors has one that "looks" like it would fit, but is too small.  The number in the Chassis Parts book is 8L-7657.  Does anyone either have an extra one I can buy or tell me where else I might find one.

Thanks, much!

Steve