I managed to squeeze enough time to wash the front CV joints today:

Next task is to fit those 4×4 Sierra outer front CV joints to Sierra 1.6 CVH rear drive shafts. Only very minor modification needed to make CV joint lock rings to hold on these drive shafts.

On the table there also is one additional CV joint which is from Ford Ka and will serve its purpose in part of the front cardan axle. So basically all the front power-train parts for my tractor are now on the table.