Sorry, but the Approved Foods list on the web site is for the regular plan. As processed grains, neither of those cereals are allowed on MWLP. Since the question was asked on the MWLP forum I assume you want MWLP cereals.
Very few dry cereals make the MWLP list. Puffed rice and other puffed whole grains are on it, and regular old-fashioned rolled oats. The MWLP book also lists something called "Crispy Brown Rice" flakes, but I've never seen them in any store.
Grape Nuts and Shredded Wheat are made by cooking the grains first, then extruding the mash into shapes and baked. That's too much processing to qualify for MWLP.
Oops! Sorry! I didn't notice that. Lol. I don't typically eat cold cereal myself, but I was just trying to be helpful.