Was still getting creaking which was gettin worse, took the swappouts off and could see there eas enough room for dirt and water to get into the interface.
The captive nuts have almost 2mm at the end with no thread so I took a file to them and removed 1.5mm of their length so as not to mess with the threaded section.
Cleaned and put a bit of grease on the mating faces of the frame and swapout and then did them up, I could instantly feel the bolts tighten up loads better as they didn’t hit a hard stop just got hard to torque, also the captive nut didn’t spin as they got tighter as they were actually being pulled tight into the swapout seat.
A 10 minute job to sort the issue once and for all