If you like the idea of seeing all of the print, select a larger (shallow) box frame. Open the back and arrange the artwork a little higher up from the middle and attach with an archival double-sided tape.
If you want to raise it slightly, use a smaller square of foam core, attach that to the backing board and then attach the print onto the top of that to raise it.
This creates interesting shadows...
Åresjön – Frozen Lake’, watercolour on raw canvas, 42cm x 45cm, 2018.
Framed using white washed oak, off-white card backing and foam-core to raise painting. Space was left around the art work deliberately. By Margaret at The Frame Spot, East Malvern, Melbourne, Australia.