I have SIBO too. It's not fun, I feel your pain. I found Primal/Paleo via SCD, so you're a step ahead of where I was! I've never done GAPS, I started out on SCD, but I had tremendous success on SCD. As for carbs, I found that I could tolerate a good amount of carrots (cooked and pureed) and squash (acorn, butternut, buttercup) in the beginning. I would pretty much eat those with every meal, mixed with some butter and salt and pepper, or some butter and cinnamon for a "treat". Like I said, I did SCD before discovering Primal, so I was eating quite a bit of the carby stuff and I was doing just fine. Although, I should also note that at that point anything was an improvement over the ridiculous amount of bloating I was accustomed to. But anyway, you should try carrots and squash in place of potatoes to see if that works for you. Just try them cooked and pureed first...raw carrots can be brutal. I'd be happy to share my SIBO/SCD experiences with you, so feel free to contact me if you want!