How do you customize which columns/fields you want included in a report (specifically the acknowledgement letter report)?
You will need to do a few things.
If you are just removing a field, you can simply just remove it from the infomaker object.
If this is an out of box report you will want to create your own local versions of the procedure, infomaker object, update t_format_info system table for the adjusted letter. It is not recommended to customize out the box reports.
Someone else can chime in if I forgot something.