I am investigating changing out my engine. is it normally necessary to remove the outdrive, or can the old engine be pulled and replacement dropped in?
You must pull the drive. When you put the new engine back in, you will have to re-align the engine. The motor mount holes are not "That" accurate. Besides, if you are off even a little bit, the coupler will go bad and you will have to pull the engine again in order to replace the $300+ coupler.