Magnetic cursor capture option when adding dimensions

Hi

   I am trying to add 'dimensions' to a PCB for documentation purposes.

   As it happens, there are 2 PTH (mounting lugs for an RJ45 connector) at the same Y offset, and X offsets +/-5.715mm.

   I would need a 'User Grid' of 5.715 here, which would need changing for similar situations.

   Also, suppose the X offsets +/-5.715mm were with respect to an 'origin X' of 1.234mm (etc). Then, I would never be able to 'land'
   the dimension cursor accurately on both PTH.

   Finally, it requires lots of very precise mouse placement.

   As the picture shows*, I fail to add the corrrect value (11.43mm).

   Can an option be added whereby the 'add dimension cursor' behaves like the existing 'magnetic tracks' option?
   In this mode, then all visible copper layers would act 'magnetically' W.R.T. the cursor. That is, the 'capture' would be
   for pad centrs, PTH centres etc.

   That way, I could easily add a dimension annotation beween two mecahnical mounting holes.

Thanks,
Regards
Stephen

*How do I add a picture please?