While removing the side steps off my parts vehicle the very last rivnut decided to slip. I was able to cut the bolt off and it's good in a way this happened otherwise I would have just assumed the frame was threaded. My '01 has the holes but no rivnuts. Are they special 'rawlbolts' or just your standard 10mm rivnut?
Discussed here: https://www.rangerovers.net/threads/rivnuts-for-fitting-side-step-brackets.24096/#post-213856

There's not much clearance under there. I'm looking at this: https://www.amazon.com/Muzata-Heavy-Riveter-Thread-250PCS/dp/B01NAGIY6X/ref=psdc_15708911_t4_B07Y698HSN

Any harm in welding them in? I was thinking just a quick touch or two.

The factory fitted item - actually more of a (steel) captive nut than a rivnut - tend to corrode and seize up solid; Would be similar (or worse) with an alloy rivnut of course, even the "heavyweight" variety.. Best to just use the holes - drill out where necessary - and use SS bolts throughout instead !?

I fitted mine with M10 stainless rivnuts, using the double spanner method. Pain in the arse but they're still solid.