How do I create custom posters in GECK using any image?

[PaladinDanser]

At the moment I am trying to take some covers from vintage gay pulp novels and books and make them into posters because the the lack of any and all NON-explicit material to decorate an interior with and I was wondering if I could get some assistance. I have looked at Candora's Box but it has the limit of the size of the image and causes it to stretch if I make it fit into their pre-made mesh. I have made the images into dds files but am stuck on how to proceed. For my purposes I am looking for this:

• ability to change the image of an existing poster and create a new file so it doesn't overwrite the existing poster, just to use the size to my advantage.

Am I able to make these changes in GECK or Vortex, or do I need another mod managing system? If at all possible I would prefer to not have to switch over to a different mod manager...

[Radioactivelad]

To avoid the stretching, just make the canvas of your new texture the same, or a multiplicative size of the original texture; and make sure to merge all layers when you're ready to export

Edited September 8 by Radioactivelad