The best way to do this is to go set up an account at http://ssa.gov and there you will see your earnings history. You can "select all" on the earnings history page, "copy" and then return to ESPlanner and click the "input earnings history" button and it will paste it all in for you. I've completed that whole process in less than five minutes before--but I also realize that setting up an account etc. is kind of a hassle.

But that's the most accurate way to do things. You'd want to do the same thing with your wife's earnings.

The program needs real earnings history in order to accurately calculate spousal benefits.

In this case, you seem to be mainly interested in your own benefits. You could guess a the earnings history until it calculates a benefit close to what you expect--but SSA tends to lowball their estimates. But given your age, it's probably very close.