The last time i had the electric kick 350 case together I discovered that a dirt crank would not accommodate the street magneto and starter clutch
. I was pretty frustrated at the time and decided to set it aside for a while. Checked a bunch of part numbers and after few ebay purchases I'm ready to try again.
Here you can see the difference between a 350 street crank (top) and dirt crank (bottom).
The 350 magneto and starter clutch (left) appears to be interchangeable with the 250 unit (right). The only difference is the 250 has 3 bolts instead of 6 holding the starter clutch on. The 350 gear has the same number of teeth as the 250 gear, but they are different.
The 350 gear is beefier and has that collar where the 250 gear is flat. You can see the 3 vs 6 bolts here better.
Incidentally, I left out a transmission gear today and had to split the case again. So I've put this case together a grand total of six times. Annoying as it is, I am getting fairly fast at assembling DR350 bottom ends