Dimension guides different length?

Is it possible to have one dimention guide shorter and one longer?

I have some point to show distance form it to symmetry line (dash and dot). The guide from that point to dimention line must be long. The second one covers the symmetry line makeing it being not dash and dot.
I can work around by drawing this longer guide manually, but it is so often need that I suppose there is right solution I don't see.

I draw one or two technical drawings a year. I used to use OpenOffice Draw. But some time ago I changed Open Office for Libre Office and when (few months ago) I tried to do a draw with LO Draw (circle setups not where you point, dimension line can't be moved more than 9mm (as I remember)) I went back to Oo for a while and drow what I needed and make decision next time I will serach some better tool. And now is that next time :).
In Oo Draw I can specify the length of each guide separatelly.

I am not familiar yet with Modify tools. In manual the Modify|Properties and Trim (I like very much) where shown, but I didn't found the way to modify guides length separatelly.

Ok. I found.

It is good to write question, and then give yourself the next try.
As this small pionts snaps at my first try it looked for me that they modify the dimensioned distance so I began looking in Modify tools for solution and didn't found :)

The extension lines (guide lines) do not react to trim or other modifying commands.
You could additionally activate "snap to entity" and when you want a short extension line on the symmetry axis then click on that somewhere at a place which gives a short extension line, you don't have to hit an endpoint or intersection.

Thanks,

I first noticed that I can modify extension lines by these small dots, and then later I noticed that if I use tool horizontal dimension line I need not to mark points which have the same Y.