You can really only do what you want *easily* with the HUD display.
First (very important) -- line up the Anchor Points of both layers with the center of the canvas (also assuming your PS image is currently centered in the canvas.) If necessary, Show Rulers and drag out guides to mark the center of the canvas. Use the Anchor Point tool (it's easy to align the up and right arrows to the guides.)
Next, select the layer (or layers) you want to move in space (this works with multiple selections too).
Open the HUD -- in the lower third of the display is a set of box icons with directional arrows -- they are controls you can use to maneuver an object in space. The basics of this are: HOLD DOWN the COMMAND key and drag on the leftmost icon to move the layer either forward or backwards in space. If you are in the active camera view, it will appear as if nothing is happening (the object is simultaneously moved in Z-space and scaled at the same time.) ...but that's just part of it:
In order to "monitor" your positioning, you need to use a split view. [Note: The *active* pane will have a yellow outline around it.]
From the Display menu (top right corner over the canvas just to the right of "View") select one of the split views. Set one view to Active Camera and one to Perspective. Orient the perspective view slightly off center so you can watch the progress. Click in the Active Camera pane to activate before using the hud/command-drag on the layer -- otherwise, it will screw up! [the active pane gets the "action" from the hud and be relative to the current viewpoint.]
Keep in mind that if you use the controls in the upper right corner of the canvas in Active Camera view, you are altering the transposition parameters of the camera. If you make any changes in *any other* view, using those controls makes no changes to camera parameters...then they're just "look" controls. Just... pay attention to which pane is active when you play around with those controls. If you need to scale the Active Camera View, use Shift - Z with the pane selected or the %scale menu over the canvas.