Thanks for the replies, I should have mentioned the current rear speakers will not be used. The QS8's will be replacing them.

It is critical that the position is correct, I rent and although I have been here for 17 years the landlord would not like the idea of me drilling 3 or 4 sets of holes in the walls.

Any suggestions on how to place them temporarily so I don't have to drill holes until I have them where I want them?

When you say just in front do you mean here where I have the crosses