It's usually the front that have 2 bolts in the lower plastic panel. Sometimes the rear do and sometimes not through the lower bumper skirt - mine have had both 2021 L405 Vogue SE 4.4 V8 DIESEL ~ #17

I had my side steps replaced recently i bought the genuien range rover ones from Sako243 from here (a big thank you).
The only struggle i had was getting the bolts off as they had rusted. Thanks to my local garage he managed to get them off.
There were no rust having taken the exsisting ones off thank god. I did however spray some tar like sealant on the under side of the new (well used) steps as mine had rusted badly from all the road salt and the time it had been on my vehicle. Some think to consider. Prior to fitting new ones. Range rover td6 54 reg touch screen

You could just replace the front mud flaps to standard one's, without the step moulding in the flap, cheapest option I would think. about �65 for a pair of genuine one's, you would need to check.