InfoPath Dev

I have a form where I need to change the column types for 3 columns in order to make the workflow work correctly. I can't change them in SharePoint unless I make them editable and I don't want to do that unless absolutely necessary. I have changed the field types in the infopath form and 'upgraded' the form. This did not change the column types after I upgraded it on SharePoint. So I did a full publish and upgraded it on SharePoint. This did not change them either.

Is there any way short of deleting the library and recreating it to upgrade the column types in my form library without making them editable?

Perhaps the upgrade might be failing due to a data type conflict re: the previous data in those columns.

What if you do this?:

1. Remove all promoted properties

2. Publish the form (check if the columns are gone?)

3. Re-add the promoted properties

4. Republish the form. (does that add the columns with the correct data type?)