I have those same rotoheads from HF, only the 1/4 and 3/8. I don't know how you would make a decision about keeping them based on what it looks like on the inside.
Anyway, they look identical to the ones pictured above by 48548. There is a heart shaped spring which holds the pawl against the out ring gear, and the "V" at the bottom of the 'heart' is how the direction selector changes directions. I don't see it in the pict, but the selector face has a protruding peg.
Anyway, the 1/4 ratchet (at least mine anyway) has the circular retaining spring. I used pick to wedge it out. I've looked a long time at the 3/8, and there is NO retaining spring, and there is NO screw holding it together. If there is, it must be under the quick release button. Otherwise I can't figure out how to take it apart. I really want to because it sounds dry inside.