Don’t do big chunks at a time. Take a little, back comb, then cut & comb out. I choose a section between the withers & half way to decide how much I want to take off / leave & work up towards ears from there then finish by working down to withers. Do lots of combing out.
I use a medium rake and use it from the opposite side the mane lies on so I don't get new mane growing on the top of the mane. Once I've got the mane as thin as I want it, I brush it back to the side it lies on and then use an old clipper blade (think its the leg plate I use) to shorten it. I back comb a small section with the blade and then sort of "chop" the end of the hair, while I'm holding it, with the blade so it cuts the hair. Not sure if my description is any good, but it works for me!!
The Solorake has differently spaced teeth on either side so gives you 2 options. I use the wider teeth first until they won’t really grab more hair then flip over to narrower side. I think it would be almost impossible to over thin with it. Once the mane gets to a reasonable thickness, it doesn’t really remove a lot of hair.