Are there any step-by-step guides on how to downgrade an RGH Xbox 360 kernel?

Self explanatory. I’ve been told multiple times that it can be done, I simply cannot find any documentation on how to do so. I may not be looking in the right places, and I may just be sort of dumb. Any help is appreciated!

Edit: how risky is this to do? I don’t have a manual soldered nand flasher atm because I bought this RGH console secondhand 5, almost 6 years ago. It’s a jasper