I recently acquired another D7 3T. The guy I bought it from said it was missing the magneto when he bought it but pop started it whenever he wanted to hear it run. Included in the deal is this core of a Bosch American MJK4/2 180A 311. At first glance it looked promising,  however curiosity got the best of me and upon further inspection it seems to be missing the distributor rotor. Not a big deal as parts seem to be available for this model but the only schematics I can find online or in my manual show what seems to be a different drive gear and I’m not sure how the rotor would fit onto the version I have. Any advice would be appreciated. 
while fiddling with the magneto and spinning the drive I noticed a rattling noise inside like there’s something loose and sometimes the drive won’t turn one way or the other. Is that normal?