Here’s a video I put together of me replacing a part on my classic Land Rover Defender 110. The rear door step metalwork was looking a little tired and it grated me, so I found this upgrade on ebay: Stainless Steel Defender Rear Door Sill Protector Trim, then went about removing the old part and fitting the new part.
This was not a hard job, but I would suggest you do not rush the job and have patience and lots of cleaning products. An electric drill would also save you time.
Enjoy my amateur video, I hope it helps you if you are planning a similar job. The part I purchased was from here.