Upgrade from ABAP 7.31 to ABAP 7.51

Hello!
I'm working on an older SAP system with SAP_ABA = 7.31. I would like to be able to take advantage of new ABAP statements introduced in 7.51.

Does anybody know how difficult it is to upgrade just the ABAP component?

Any pointers to documentation for this upgrade scenario (7.31 to 7.51) and/or feedback on your experiences while doing such an upgrade will be appreciated!

Thank you.

---Hugo