I recently needed to replace the master cylinder for the clutch. The screws holding the pedal cover should go into captive nuts but these are long gone. They have been replaced by a washer and nut being very difficult to access deep down in the footwell.
I found some rivnuts on eBay which are available in various sizes – i went for M6 size being closest to the original imperial screws.
I mounted the rivnuts onto an M6 bolt with a nut to clamp the rivnut into the hole which i had to drill out to 12mm to fit the nut.
Very pleased with the finished result which is going to save a lot of grazed knuckles and some choice words trying to access nuts under the dash in the footwell.