I see now that people have had less luck with these, and advises people to use original Cosworth.

Since the accident already is out, can i move the new sierra xr CV joints onto my Old Cosworth front Drive Shafts. its the drive shaft itself that is 10mm longer? CV joints are the same as the original Cosworth?

Since my car will have ahmed springs it is probably too high for these long drive shafts. the xr ones

 

10 cm uprated shafts were too long, as many have experienced.
there is no problem putting the new knots / joints on the old shafts.
perfect "new" old complete axles in the original length.