You're welcome, Electrosmash is an awesome resource! I think the RAT is going to be a little tougher than the fuzz but it's definitely still doable. Just take it slow and build it in small segments. It's really hard to find the original LM308 chip that was used in the original models but I've built one with the more attainable OP07 that was used in later models and it still sounds awesome. This is what I use for breadboarding. It's got room for just about anything you could come up with.