You can use it under an A but it requires quite a bit of work. First off it is too wide if you use fenders, the torque tube is too long and you either have to extend the frame or move the spring mount. You can mount the brakes on the A reared but have to notch the backing plate to clear the spring mount.
Thanks for the info! The brakes are the only thing I was hoping to use so it sounds like I'm in luck.