So i have two issues. first is which way is up? the shaft through the center is offset and i am not sure if is should be offset upwards or offset downwards.
The bigger issue is the new inserts are slightly smaller than the old ones. they just fall in place and don't press at all. does anyone know what i should be doing to put the replacements in properly?

There is no offset on the spool mounts the sleeve for the bolt is centerline to the 'oval' in the metal bracket... If they slip in, then they must be for pressing into the existing sleeve for the old rubber mount (take propane or MAP gas torch and burnout all the old rubber).

Since the new replacement rubber doesn't hold up too well to performance slants, I would suggest Mr.Spiva at Polybushings.com...
Haven't had a problem with these yet in either duster...

-D.Idiot