I managed to get my hands on one, which was fitted to a bumper, but I broke it when trying to remove it - how does one remove it without damaging it?

Try pushing upper edge of the cover inwards.

Press outer edge for the front cover.

Edited 10 March10 Mar by Warrior193
correction

You mean the No4? parallelogram cover?

https://www.catcar.info/

2 minutes ago, D.FYLAKTOS said:

You mean the No4? parallelogram cover?

https://www.catcar.info/

Yes

What do you see? it's missing from many Felicia.

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcR4O-1arEBcXIzphWIvGjNtU_uD92TcBgHwRw&s

Including mine because after few years every small bumper hit will make it pop out sometimes drop down in the street, that's why many Felicias here haven't it on.

The 2 clips in the bottom after few clip-unclip are prone to brake or bent.

If you find a used one in the same colour and glue it you can not remove it in case you want to tow someone else, if you go to a repair-shop can stitch it from in the back with some Π style upholstery nails but also in case like above you can not remove it.

As i see it and since you want to be removable 2 layers of Tesa strong self-adhesive tape in the back of the bumper is the best solution, will keep it steady till you need it one day.