ITR Form -schedule S salaries

HI ,

I am filling up the details for Schedule S in ITR form with 3 Form 16s..

I found two different set of instructions ..

1. One said repeat the details 1 through 6 for each employer and enter the Total income from Salaries at last.

2. Another said enter just the details of the last employer / employer with highest salary.

So in this case how should i enter to make Schedule S reflect my Total Income from Salaries .

3. Generally , Is the customization of ITR forms for e.g add extra rows (as for Schedule S / Schedule TDS ) allowed ?.

Which one should i follow. Pease let me know.

Thanks,