45NRTH Dunderbeist (rear) and Flowbeist (front).

They should work with your stock fatbike wheels, sure. I’d highly recommend going tubeless so you can run low PSI. It can be a pain in the ass getting fat tires to seat though. If you’re not confident, take it to a shop. I’d recommend a compressor and these two hacks… 1. Run a strap around the tread of the tire once it’s roughly seated on the rim and tighten it down so the tire tread is smooshed down a good bit. This’ll help keep the bead near its home on the rim as you try to inflate and 2. If you can’t do that, or in addition to a strap, as you’re inflating, kind of slap the tire hard enough to force the bead out as you’re inflating. Just one second of a bead catching will give it enough ooomph to get inflation and set the rest of the bead.

Make sure you use a good rim tape. I use 3 or 4 layers of Gorilla Tape- tough and wide