Some ratchets are better at getting into the small spaces than others. This thread is dedicated to them. I'll start off with a few please post what you've got.
In general I think these are the smallest 1/4 drive I have. The Plomb 4751 is about the tiniest I've ever seen but they seem to be very delicate. Almost all I've ever seen are broken in one or both directions, This one is functional but I'll never use to break anything loose or tighten anything up very tight. If you've ever seen the pawls they are very thin that's why they are so delicate. Blackhawk 24991 perhaps my favorite of the lot, Wright 90, Thorsen 77M, Wright2426, unmarked, Rich (?) R1, Williams Superatchet M-51 another of my personal favorites.
Just for scale