OOh... then what I did is right for now...the depth is 12 feet from the front wall to the rear cupboards.
Till I figureout a good way to mount the PJ, i kept it in one of the cupboards.
The below pic is my rear wall... the problem is that entire rear wall is covered with cupboards. And there is a false cieling on top... i have one or two ideas for mounting though.. il post the pics if i succeed.