I ended up overpaying the max SS for the year. How do I file to use that overpayment to cover my owed income tax?

It should be automatic.  Check 1040 Schedule 3 line 10 for it.  Then Schedule 3 goes to 1040 line 31.

Did you have more than 1 Employer?  If you had more than 1 employer and paid more than $8,537.40 in social security tax (box 4) combined you get the excess back on your tax return.  And the max is per each person not together for a Joint return. So be sure to assign each W2 to the right spouse.

On the W-2 form, fill out all boxes.   When you show the overpayment in the box for SS, it will automatically roll to last page just like amount withheld.   (amount of SS overpaid)   They will be added together and then subtract the amount you owe.

however, if 1 employer over-withheld social security then you can only get it back from the employer.