Drop down menu to show only related project contacts

To simplify my app I have a Projects and Contacts table where each project can have multiple contacts. I have a specific form in the Project table called Closeout. The form is a series of questions someone from my company fills out while talking to the Contact. One of questions is to select the specific contact they talked to from a drop down list.

When a Contact is created the are assigned to a specific Project. What I am looking to do is have a drop down menu on the closeout form that lists only the project related contacts and not all contacts in the table. 

I made a reverse table relationship (one contact may have multiple projects) and then used the Related Contact (reference) field to display the drop down list on the form. I used the default record picker and also made an embedded table report but in both cases the drop down list shows all Contacts in the table, and not just the ones that are specifically related to the project.

How do I make the drop down menu only show the contacts that are specifically related to the project? What am I missing?

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David Hoover
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