Adding a custom field to T510W table

Hi friends

we have a requirement in which we have add ZZTRFGR Pay group to t510w table by appending structure.

Now How can we populate value to it? as the standard V_t510W does not allow to customize it .

so now in the table ZZTRFGR field is remaining blank. They have proposed 3 solutions which one would be the best?

1.SAP created an view V_T510W and created an table maintenance generator with more functionalities like "Delimit","Collapse" and TEXT for each field available in T510w ,for the extra field(ZZTRFGR) to bring we need to build separate module pool program with all features sap created,

2. via LSMW to update it

3. write a ABAP code to update via flat file?

Which one would be easier with less effort??

with regards

Sony