Lindsay Lohan goes before  Judge Stephanie Sautner tomorrow for her second probation progress report and she will once again pass with flying colors ... but this time it came down to the wire ... sources tell TMZ.

As the judge dictated back in November, Lindsay was required to complete 12 morgue visits and 4 psychotherapy sessions by Tuesday's court hearing. Sources close to Lindsay tell us she's done just that ... but she completed the last 2 morgue visits on Friday and Saturday.

According to our sources, Lindsay has been a model morgue employee.  Translation -- She gets the job done with no drama and she's friendly with the staff.

After tomorrow's hearing  Lindsay will be at the halfway mark of her probation. She has another hearing February 15, where she'll have to show proof she completed another 12 morgue visits and 4 therapy classes. And on March 29 -- her final hearing -- she must show she's completed the remaining 17 morgue visits and 6 therapy classes.

Should Lindsay slip up at any point, she gets 270 days behind bars.

We'll be in court tomorrow.