This post is way late for Robert N, but since a search engine sent me here when I was looking for the same info:
Model AC-552 was also sold by Regency Fans, round about 1997-2000, and you can get a manual for a virtually identical fan from www.regencyfan.com. (Depending on what yours looks like, you can use the manual for "Professional", "Patio Pro", or "Marquis/Countess Series". The main difference is that you might need to buy an S-hook to temporarily hold up the hugger-mounted motor while wiring it, if your mounting bracket doesn't have a built-in hook as pictured.) You will need 3 hugger scrrews which were probably discarded when the rod installation was done. These (firmly!) attach the canopy directly to the motor housing. Pull the plastic trim ring off the bottom of the canopy to see the holes; 3 are to fit over screws sticking up from the housing, and 3 are for the hugger screws to fasten it. Other than that, just follow the rod-mount instructions in the manual *backwards* to get the set-screw, cotter pin, and ball/collar/canopy off in reverse order. You might also need to cut the wires shorter, assuming your hugger installation is permanent and you aren't going back to a rod in another 7 years... Good luck and read the manual first!