Not exactly. I have a stand alone table and I want to use the "Display X Y Data" tool so I can create a feature class based on that table which has CR05 coordinates. The tool creates points for each line of the table and it automatically assigns a position based on the coordinates. I thought that if I could "change" the WGS84 default coordinates in the map, then the tool would work only using the CR05 system and I would not get the error message that I'm receiving. But I think now that if I want to create that feature class that way is better if I transform the coordinates to WGS84 first (not sure how to transform so many lines) and then use the tool; which works with WGS84.
And I thought that if could see the CR05 coordinates on the cursor it would be easier for me, I could use the Locate tool any time I wanted to check where a borehole was based on the coordinates on the geologic reports. That's why I was so interested in "forcing" the coordinates to be CR05. I'll be working solely on that system.
Btw: Is there a better way to insert points from a different coordinate system? Let's say, Cad maybe?