Sierra rack

[XR4BILL]

I have a Merkur lefthand rack (Sierra). Also Merkur Diff (Sierra).
If the rack has to be shortened by 19cm, is it possible to make the frame a little wider say (10cm) and reduce the 19cm to say (9cm). Then use spacers in the rear driveshafts/hubs? (these numbers are just guestimated at this time)
Or would this compromise the build in other areas? ie Body panels to be adjusted accordingly.
(Not started my build yet, just gathering some information and bits and pieces)

cheers,

Bill