Originally Posted by John V6
Yes reusable.

Similar to these on the back panel
[Linked Image]

Thanks. Now I can see what I am dealing with - friction plugs. I guess the wooden frame into which they secure can swell and grip them tight. Anyway I will attack them with renewed resolve later today!

2020 PLUS FOUR
2010 Land Rover Defender 2.4 90 Soft Top
2018 BMW 740LD
2022 BMW i3