I did couple of yrs back. Yea it takes some serious time and info to fill those up. I am pretty sure all those mnavi guys filled it up too.

My suggestion fill all those completely and clearly . When they come for interview they ask each and every details again. And regarding federal job, don't know which industry you are in , but if you get GS-13 or 14 level job it will be pretty chill . If you start from little low, it will take forever to climb up.