Can I align clones between pictures?

PS6 on XP.

I have 2 nearly identical pictures (1 edited). I need to clone small details
from picture A to picture B. While cloning from picture to picture is easy, I
need the clone to be exactly aligned between pictures. In other words, if my
clone starts at pixel x-y of picture A, I need the destination to be exactly the
same pixel x-y in the destination picture. The x-y in the source will dictate
where the pixels are cloned to in the destination picture, not where I click in
the destination.

Is it possible to perfectly align clones from picture to picture? I'm assuming 2
pictures of identical sizes.

Thanks.

No, you have to alt-click on the source layer and that sets the source x-y
location. Then you switch to the other layer and you have to click drag to do
the clone and it clones to the x-y of the mouse position, not the matching x-y
of the source.

So if you alt-click on the upper right of the source layer, switch to the
destination layer and click drag in the lower right, you'll be cloning from the
upper right to the lower left. Not aligned at all.

The layers work the same as when different images are used. There seems to be no
way of synchronizing the x-y of the clone source and destination.

If your two images are exactly the same size, I would think you could do this by
having both images as layers in one file. Put the source image on the bottom,
the destination on the top. Select the area from the source and copy to a new
layer. Move that new layer to above the destination layer and merge that layer
down onto the destination layer.

I would think you could also do this even if the images are not exactly the same
size if you can align the two images exactly where you want them to be aligned
before doing this operation. (Such as by reducing the opacity of the upper layer
and visually aligning them, although there may be a more precise way to do this
is you need per pixel accuracy.)