Reporting full page header

Trying to make a report that utilizes a table to first group data using one of the columns in my query dataset. I want to make a full page unstructured header in the report from that group then add another full page unstructured body generated for each row in the group. How do I do that? My problem is that I can’t extend the table header to the full page or there won’t be room for the body in the designer and I can’t extend the body to a full page or there won’t be room for the header in the designer…

I tried designing the header then change its height to zero before designing the body and it kinda works, it’s just that the first body is created on top of the header when the report is generated. Every page after that is created on a new page as expected.

Hope I managed to explained my problem and I really hope someone can help!

Added additional information about what I want.
The report is for making product load certificates from load test data. The machine has a certificate for the load cell (verified by 3rd party and is renewed every year) that is stored as an image (the machine_lc_certificate column, see below).

This is my table data key and the grouping done by column ‘machine_lc_certificate’.
image image

This picture shows about what I want to achieve. As I write on the picture both the group header and the body needs to extend a full page. The final result should be a report that contains all products tested in a single order. As tests can be done on different machines (different load cell certificates) or the load cell certificate can be updated between two tests the report should contain a load cell certificate (the group header) followed by generated product certificates.

I hope this makes more sense.
Having a hard time explaining myself

Might be good if you could post some screenshots of what you currently have and mockups of what you want. Little hard to picture what you are trying to do.

Thank you, edited the post to contain more info

As of right now, I took the second best approach I can think of.

Made it a table group and added the grouping before the product reports.
image image image

Now it generates all pages with loadcell certificates (one time per certificate type) used for product testing before generating the product certificates. Not exactly what I wanted but I guess it works.