Most of it (at the moment) is converting an array index (i.e. 0 to 80) into a cell reference (i.e. (0, 0) to (8, 8)) and a graphics coordinate (i.e. (0, 0) to (280, 280)).
I've got it displaying the things I want but they are displaying a bit all over the place at the moment.
Hmm... I suppose I could write a class that does all of the work for me so I only need to do it in one place. That would make more sense I suppose.
Call it Converter and have methods to convert from cellref into index and vice versa and also cellref (or index) into coordinates, etc...
That way I can just plug all my other classes into it and all the maths is in one place instead of several.