inserting a matrix greater than 3x3 using "equation tools"

[jhale]

Using the equation editor to embed a matrix equation into text. The biggest matrix offered in the tool bar is 3x3. Is it possible to make a bigger matrix?

I want to make 6x6. I have tried making a 2x2 and then putting a 3x3 matrix into each place holder cell. That works, but that does not preserve alignment when I insert symbols into the place holders.

Any suggestions?