Data blocks single user

Morning…
I have one of those chores today of importing dxf file with 4 curves…
making them mesh… setting the origin points on each…
rotate and scale…
then extrude…
then repeat this process with the following dxf…
each dxf has 4 of the same curves, as future objects, just different geometry.

to stream line this activity I take the prior 4 extruded, duplicate them…
then go into the data block and try to replace the mesh with the newly imported dxf after a rotate and scale apply…

BUT its not a single user.
therefore I need to make another by pressing the 2 on the right of the name. but this just makes a copy… after a while I am looking at a ton of orphans, and I know quitting and restarting will fix this… but that just adds to the list of unnecessary actions in this tedious activity.
there must be a way to just make it a single user without duplication.

does anyone know the structure well enough to point me in the right position to remove this speed bump?

cheers

In the outliner you can delete orphans. There is a drop down menu in the outliner where you can chose “orphan data”.