126 film is the same width as 35mm. My first camera was an Instamatic, and that's the one on which I first learned to process film and print. When you go dark and crack the cartridge open, you'll find the film and a paper backing in one side. The image is essentially or exactly the same in the short dimension, but it's square. As I recall, there's only one sprocket hole per frame, too, and only on one side. You should be able to use your 35mm reels and negative carriers with it. I shot beau coup verichrome pan with mine back in the 70's before I upgraded to a Mamiya Sekor 35mm.