You will need to use the drive adapter and muffler off of your original engine. You may have to use the oil filter bracket as well and the wiring may be slightly different. You may also have to use other minor parts off of your current engine. If you use the 356447 engine, you can remove the regulator and use your current one if yours has the 16 amp charging system on it. Also the flywheel fan and blower housing is 1-3/8" thicker on this engine than the 294447 series. If this is a problem for you, the parts off of your original engine would work on it.