Hi Amar,
Have you used this shift/aplha conversion in both master data and transactional data loads?
Other option would be to do this in the source system itself - but we need to do this in all the master data and transactional data where the XARLPROD is used. We initially had the same requirement in one of my project and as it was becoming more complex we used the SPM as in the standard.
Best regards,
Prasanna