DataGridView idea/problem

Question

I've implemented a DataGridView and I have rewrote the DataGridViewCell class, as it is primitive.
Now I am adding specific information (time specific) to certain cells, and I want to layer each cell so that the box added to the cell will sit, according to the time allocated, to the cell.
E.g. if the information was for 12 midday then the box of information will reside in the middle of the cell etc.

Any suggestions on the layering of the cells?

Thanks in advance

Urema.