There are practically no differences between the USDM Prizm and Corolla. I believe the dash layout may be a little different, then you got the grille, bumper ant tail lights. Other than that - they are identical.
Same as here with the Holden Nova. Just a few cosmetic things...
With the Half-cut, the reason why its so different is because its made for the JDM. It's different to practically anything out there. Even if it is the same year... I had the same problem when i got my half cut. But both mine and the half-cut being RHD - I just made custom mounts and fitted the dash