I, too, was worried about doing autopsies because I really disliked anatomy M1. I greatly disliked dissecting out tiny things that I spent hours trying to find and was assured looked completely different in a live (or freshly dead) person, our cadavers grew mold, dried out, ect. And the smell never left your clothes. And took about 2 showers to get out of your skin. The ventillation was poor but the fans kept the room sickly cold. And you would get light headed if you spent too much time in there.
I found that while no one will make a perfume out of the odors coming from an autopsy suite or grossing room, the smells are very different. If the autopsy is a freshly deceased person, the bowels will be the worst part. Otherwise, it can get pretty bad (you will wish it smelled like cadaver) but the smell comes out after one wash, you have more personal protective equipment, and there is a purpose/ puzzle as to why you are doing the case. I actually enjoyed assisting despite the smell. I even liked the evisceration.
Grossing smells more like the cadaver lab because of the formalin. But most of the places I went ventillated their grossing areas much better than my med school ventillated its cadaver lab. Grossing under a hood helps. Again, more personal protective equipment, and the smell goes away faster (one wash). And here you are dealing with at worst a whole organ or area not a whole body. And you get to see what you grossed under the scope, play a role in patient care, ect. I found that having purpose to the exercise helped my enthusiasm.
No matter where you do your residency, there will be plenty of grossing and autopsies to do and learn from; though few people really look forward to these things, you do them for more than a few months.
Once an attending in academics or in private practice, you can get more choosy. The other people that responded would know more about that.
My perspective is only that of a fourth year medical student. I had similar reservations and so made a point of getting in to assist in these "unpeasant" things. I got as much exposure as I could to make sure it was something I could handle. I actually discovered that I really enjoyed them. I found it completely different from the cadaver lab.
Add on: the people who liked the cadaver lab most in my class as an M1 mostly went on to do surgery.