Roof trim, hidden bolts - three the same one different!

[fourwheels]

Hi, I've just sold my 2002 2.0l diesel mondeo estate and now have a 2008 1.8l diesel estate.

The mondeo had roof rails onto which I attached a roof box via roof bars.

The focus has flush roof trim on either side in which each trim has a forward and a rear blanking plate about 15cm / 6" long.

I was told that I could attach roof bars using these blanks. By turning the screw in each blank through 90 degrees this allows the blank to come off. Underneath there are threaded holes which each foot attaches to via a single bolt.

All went well at first with three of the feet bolting to the threaded hole. However on removing the last blank, instead of finding a threaded hole I found a 22mm hole which seems to expose the underside of the roof lining.

I have been to Ford who say they have no info or diagrams of even the roof with its threaded holes and suggest that there are expandable blanks which go in to a 22mm hole to fit roof bars. I have read a description on line which refers to having to remove the roof lining to drill out 22mm holes for roof rails but does not describe the inserts which go into the hole. A photo would help.

With three existing holes with three captured threads and a gaping 22mm hole I can't do anything. It looks like someone has started the job and then given up after one hole. The roof lining shows no sign of removal and is pristine. The roof exterior paintwork shows no sign of damage either.

Can I put an insert in the 22mm hole and If so where do I get it ?Do I need to drill out the other three?

Would appreciate any info to know how to solve it for a roof bars or how the fourth thread has been replaced with a 22mm hole.

My thanks